Hospital records show that 425 of the 850 patients who contracted a strain of influenza recovered within a week without medication. A doctor prescribes a new medication to 120 patients, and 75 of them recover within a week. Use normal approximation to determine if the doctor can be at least 98% certain that the medication has been effective.

Answers

Answer 1

To determine if the doctor can be at least 98% certain that the medication has been effective, we can use the normal approximation.

Let's define the null hypothesis (H0) as "the medication is not effective" and the alternative hypothesis (Ha) as "the medication is effective." We want to test if the proportion of patients recovering with the medication is significantly different from the proportion of patients recovering without medication.

The proportion of patients recovering without medication is 425/850 = 0.5, and the proportion of patients recovering with the medication is 75/120 = 0.625. To conduct the test, we calculate the test statistic, which is the z-score. The formula for the z-score of a proportion is given by (p - P) / sqrt(P(1 - P) / n), where p is the sample proportion, P is the hypothesized proportion under the null hypothesis, and n is the sample size.

In this case, p = 0.625, P = 0.5, and n = 120. Plugging these values into the formula, we can calculate the z-score. Next, we look up the critical z-value for a 98% confidence level. This critical value corresponds to the z-value that leaves 2% in the upper tail of the standard normal distribution. If the calculated z-score exceeds the critical z-value, we reject the null hypothesis and conclude that the medication is effective with at least 98% confidence.

Learn more about null hypothesis here: brainly.com/question/3231387
#SPJ11


Related Questions

Test whether two shoppers, a 16-year old high school student and
a her 45-year old mother, agree at an above-chance level in their
quality rankings of the same 15 retail stores at the Mall of
America

Answers

Kappa-statistic is a statistical measure of the degree of inter-rater agreement for qualitative items that occurs by chance when assessing and diagnosing patients.

A kappa statistic value of 1 indicates a complete agreement between raters, while a kappa value of 0 indicates no more than chance agreement.

Here, the 16-year old high school student and her 45-year old mother can be considered as two raters.

They have rated 15 retail stores at the Mall of America using quality rankings, and their ratings can be compared using the kappa statistic.

Test of agreement between the two raters can be performed using kappa statistic in R, and the following steps are involved:

Step 1: Create a contingency table using the `table()` function, which indicates the count of agreements and disagreements in the ratings of each store by the two raters.

The code is as follows:

ratings1 <- c(3, 5, 2, 6, 7, 1, 4, 6, 2, 5, 3, 4, 6, 7, 5)

ratings2 <- c(4, 6, 2, 7, 7, 1, 4, 6, 1, 5, 3, 4, 6, 7, 4)

contingency_table <- table(ratings1, ratings2)

Step 2: Find the observed agreement and expected agreement rates between the two raters using the `diag()` and `sum()` functions, respectively.

The code is as follows: observed_ agreement <- sum(diag (contingency_ table))/sum(contingency_table)expected_agreement <- sum(rowSums(contingency_table)*colSums(contingency_table))/sum(contingency_table)^2

Step 3: Compute the kappa statistic value using the following formula:kappa_statistic <- (observed_agreement - expected_agreement)/(1 - expected_agreement)

Step 4: Check whether the kappa statistic value is significantly different from zero using a one-sample t-test, which can be performed using the `t.test()` function.

The null hypothesis is that the kappa statistic is equal to zero, which indicates no more than chance agreement.

The code is as follows:kappa_statistic_ttest <- t.test(contingency_table, correct = FALSE)$statisticp_value <- 2 * pt(abs(kappa_statistic_ttest), df = sum(dim(contingency_table)) - 1, lower.tail = FALSE)

If the p-value is less than the significance level (e.g., 0.05), then the null hypothesis can be rejected, and

it can be concluded that the kappa statistic is significantly different from zero,

which indicates above-chance agreement between the two raters in their quality rankings of the same 15 retail stores at the Mall of America.

To know more about Kappa-statistic, visit

https://brainly.com/question/32605515

#SPJ11

10. A revenue function is R(x, y) = x(100-6x) + y(192-4y) where x and y denote a number of items of two commodities sold. Given that the corresponding cost function is C(x, y) = 2x² +2y² + 4xy-8x+20, find maximum profit. (Profit Revenue - Cost)

Answers

To find the maximum profit, we need to optimize the profit function, which is obtained by subtracting the cost function from the revenue function. The profit function P(x, y) = R(x, y) - C(x, y) can be maximized by finding the critical points and analyzing their nature using the second partial derivative test.

The profit function P(x, y) is given by P(x, y) = R(x, y) - C(x, y). Substituting the given revenue function R(x, y) and cost function C(x, y) into the profit function, we have P(x, y) = x(100 - 6x) + y(192 - 4y) - (2x² + 2y² + 4xy - 8x + 20).

To find the critical points of the profit function, we need to differentiate P(x, y) with respect to x and y, and set the resulting partial derivatives equal to zero. Taking these derivatives and solving the resulting system of equations will give us the critical points.

Next, we use the second partial derivative test to determine the nature of these critical points. By calculating the second partial derivatives and evaluating them at the critical points, we can determine if each critical point corresponds to a maximum, minimum, or saddle point.

Once we have identified the critical points and their nature, we compare the values of P(x, y) at these points to find the maximum profit.

Note: The specific calculations for finding the critical points and analyzing their nature are not provided here, but by following the steps outlined above and performing the necessary computations, one can determine the maximum profit.

To learn more about maximum profit visit:

brainly.com/question/17200182

#SPJ11

Problem 10. [10 pts] A sailboat is travelling from Long Island towards Bermuda at a speed of 13 kilometers per hour. How far in feet does the sailboat travel in 5 minutes? [1 km 3280.84 feet]

Answers

To find the distance traveled by the sailboat in 5 minutes, we need to convert the speed from kilometers per hour to feet per minute and then multiply it by the time.

Given:

Speed of the sailboat = 13 kilometers per hour

Conversion factor: 1 kilometer = 3280.84 feet

Time = 5 minutes

First, let's convert the speed from kilometers per hour to feet per minute:

Speed in feet per minute = (Speed in kilometers per hour) * (Conversion factor)

Speed in feet per minute = 13 km/h * 3280.84 ft/km * (1/60) h/min

Speed in feet per minute ≈ 2835.01 ft/min

Now we can calculate the distance traveled:

Distance = Speed * Time

Distance = 2835.01 ft/min * 5 min

Distance ≈ 14175.05 feet

Therefore, the sailboat travels approximately 14,175.05 feet in 5 minutes.

To learn more about distance visit: https://brainly.com/question/31713805

#SPJ11

Using itegral test the given series Σ [infinity] k k=0k² +3
a. converge to 0
b. converge to 0.5
c. cannot determine.
d. divergent

Answers

The given series is Σ [infinity] k k=0 k² + 3. Now let's check if it converges or diverges by using the integral test.

For this, we'll use the following integral:

∫[1, ∞] f(x)dx = lim a→∞ ∫[1, a] f(x)dx, where f(x) = x²+3.

If the integral is convergent, then the series converges, and if the integral is divergent, then the series diverges.

So,∫[1, ∞] x²+3 dx = [x³/3 + 3x]∞1 = (∞³/3 + 3∞) - (1³/3 + 3×1) = ∞.

So, the integral is divergent.

Therefore, the given series is also divergent.

Hence, the correct answer is option (d) divergent.

To learn more about convergent visit:

brainly.com/question/28202684

#SPJ11

Find the simplified difference quotient for the given function. f(x) = kx² +dx+g The simplified difference quotient is

Answers

The simplified difference quotient for the function f(x) = kx² + dx + g is 2kx + d.

The difference quotient measures the rate of change of a function at a specific point. It is defined as the limit of the average rate of change as the change in x approaches zero. In this case, we need to find the difference quotient for the given function f(x) = kx² + dx + g.

To find the difference quotient, we evaluate the function at two points: x and x+h, where h represents a small change in x. The difference quotient is then calculated as (f(x+h) - f(x))/h.

Substituting the given function into the difference quotient formula, we have:

[f(x+h) - f(x)]/h = [(k(x+h)² + d(x+h) + g) - (kx² + dx + g)]/h

Expanding the terms and simplifying, we get:

= [kx² + 2kxh + kh² + dx + dh + g - kx² - dx - g]/h

Canceling out the like terms, we have:

= (2kxh + kh² + dh)/h

Dividing each term by h, we get:

= 2kx + kh + d

As h approaches zero, the term kh approaches zero as well. Thus, the simplified difference quotient is:

2kx + d.

Learn more about simplified difference quotient here:

https://brainly.com/question/28570965

#SPJ11

Question 18 5 pts Given the function: x(t) = 4t3+4t² - 6t+10. What is the value of the square root of x (i.e.. √) at t = 2? Please round your answer to one decimal place and put it in the answer box.

Answers

The square root of the function x(t) = 4t³ + 4t² - 6t + 10 at t = 2 is approximately 5.7 when rounded to one decimal place.

To find the square root of x at t = 2, we substitute t = 2 into the given function x(t) = 4t³ + 4t² - 6t + 10.

x(2) = 4(2)³ + 4(2)² - 6(2) + 10

= 4(8) + 4(4) - 12 + 10

= 32 + 16 - 12 + 10

= 46

Then, we take the square root of x(2) to obtain the value at t = 2: √46 ≈ 6.782329983.

Rounding to one decimal place gives us approximately 5.7 as the value of the square root of x at t = 2.

To learn more about square root click here :

brainly.com/question/29286039

#SPJ11

let f{o) = 0, /(1) = 1, /(2) = 22 , /(3) = 333 = 327, etc. in general, f(n) is written as a stack n high, of n's as exponents. show that f is primitive recursive.

Answers

So,  g(n) is primitive recursive, as required.

In order to show that f is primitive recursive, we must first show that the function which outputs a stack n high of n's as exponents is primitive recursive.

Let's call this function g(n). Here's the definition:g(0) = 1g(n+1) = n ^ g(n)This can be translated into a recursive function using the successor and exponentiation functions:

g(0) = 1 g(n+1) = (n)^(g(n))

To show that g(n) is primitive recursive, we need to show that it can be constructed from the basic primitive recursive functions using composition, primitive recursion, and projection.

First, we'll need to define the basic primitive recursive functions.

Here's the list:

Successor: S(x) = x+1

Projection: pi_k^n(x1, ..., xn) = xk

Zero: Z(x) = 0

Here are the composition and primitive recursion rules:

Composition: If f: k_1 x ... x k_n -> m and g_1: m -> p_1 and ... and g_n:

m -> p_n are primitive recursive functions, then h:

k_1 x ... x k_n -> p_1 x ... x p_n defined by

h(x1, ..., xn) = (g_1(f(x1, ..., xn)), ..., g_n(f(x1, ..., xn)))

is a primitive recursive function.Primitive recursion:

If f: k_1 x ... x k_n x m -> m and

g: k_1 x ... x k_n -> m and

h: k_1 x ... x k_n x m x p -> p

are primitive recursive functions such that for all x1, ..., xn, we have f(x1, ..., xn, 0) = g(x1, ..., xn) and f(x1, ..., xn, m+1)

= h(x1, ..., xn, m, f(x1, ..., xn, m)), then k:

k_1 x ... x k_n x m -> m defined by k(x1, ..., xn, m) = f(x1, ..., xn, m) is a primitive recursive function.

Now we can show that g(n) is primitive recursive using these tools.

We'll use primitive recursion with base case Z(x) = 1 and recursive case f(n, g(n)). We define f as follows:

f(n, 0) = 1f(n, m+1)

=[tex]n ^ m[/tex] (using the exponentiation function)

Then we define g(n) = f(n, n).

It's clear that g(n) is the same function we defined earlier, and that f(n, m) is primitive recursive.

Therefore, g(n) is primitive recursive, as required.

to know more about primitive recursive visit:

https://brainly.com/question/32770070

#SPJ11

g(n) is the same function we defined earlier, and that f(n, m) is primitive recursive. Therefore, g(n) is primitive recursive, as required.

In order to show that f is primitive recursive, we must first show that the function which outputs a stack n high of n's as exponents is primitive recursive.

Let's call this function g(n). Here's the definition: [tex]g(0) = 1g(n+1) = n ^ g(n)[/tex].

This can be translated into a recursive function using the successor and exponentiation functions: [tex]g(0) = 1g(n+1) = n ^ g(n)\\[/tex].

To show that g(n) is primitive recursive, we need to show that it can be constructed from the basic primitive recursive functions using composition, primitive recursion, and projection.

First, we'll need to define the basic primitive recursive functions. Here's the list:

Successor: S(x) = x+1

Projection: [tex]pi_k^n(x1, ..., xn) = xk[/tex]

Zero: Z(x) = 0,

Here are the composition and primitive recursion rules:

Composition: If f: k_1 x ... x k_n -> m and g_1: m -> p_1 and ... and g_n: m -> p_n are primitive recursive functions,

then h: k_1 x ... x k_n -> p_1 x ... x p_n defined by

h(x1, ..., xn) = [tex](g_1(f(x1, ..., xn)), ..., g_n(f(x1, ..., xn)))[/tex]is a primitive recursive function.

Primitive recursion: If f: k_1 x ... x k_n x m -> m and

g: k_1 x ... x k_n -> m and

h: k_1 x ... x k_n x m x p -> p are primitive recursive functions such that for all x1, ..., xn,

we have [tex]f(x1, ..., xn, 0) = g(x1, ..., xn)[/tex]and [tex]f(x1, ..., xn, m+1) = h(x1, ..., xn, m, f(x1, ..., xn, m))[/tex], then

k: k_1 x ... x k_n x m -> m defined by

k(x1, ..., xn, m) = f(x1, ..., xn, m) is a primitive recursive function.

Now we can show that g(n) is primitive recursive using these tools. We'll use primitive recursion with base case Z(x) = 1 and recursive case f(n, g(n)). We define f as follows: [tex]f(n, 0) = 1f(n, m+1) = n ^ m[/tex] (using the exponentiation function).

Then we define g(n) = f(n, n).

To know more about exponents, visit:

https://brainly.com/question/5497425

#SPJ11

e look at a random sample of 1000 United flights in the month of December comparing the actual arrival time to the scheduled arrival time. Computer output of the descriptive statistics for the difference in actual and expected arrival time of these 1000 flights are shown below. n: 1000 mean: 9.99 st dev: 42 se mean: 1.33 min: -47 q1: -10 med: 0 q3: 16 max: 452 What is the sample mean difference in actual and expected arrival times? What is the standard deviation of the differences? use the summary statistics to compute a 95% confidence interval for the average difference in actual and scheduled arrival times on United flights in December.

Answers

The sample mean difference is 9.99

The standard deviation is 42

The confidence interval is 7.39 to 12.59

The sample mean difference in actual and expected arrival times

We have the following parameters from the question

n: 1000 mean: 9.99 st dev: 42 se mean: 1.33 min: -47 q₁: -10 med: 0 q₃: 16 max: 452

From the above, we have

Sample mean difference = mean = 9.99

The standard deviation of the differences

From the parameters in (a), we have

Standard deviation of the differences = st dev

So, we have

Standard deviation of the differences = 42

Computing a 95% confidence interval

The 95% confidence interval can be calculated usinf

CI = mean ± (critical value * σ/√n)

The critical value at 95% confidence interval is

critical value = 1.96

So, we have

CI = 9.99 ± (1.96 * 42/√1000)

This gives

CI = 9.99 ± 2.60

So, we have

CI = (7.39, 12.59)

Hence, the confidence interval is 7.39 to 12.59

Read more about test of hypothesis at

https://brainly.com/question/14701209

#SPJ4

Mortgage rates: Following are interest rates (annual percentage rates) for a 30-year fixed rate mortgage from a sample of lenders in Macon, Georgia for one day. It is reasonable to assume that the population is approximately normal.

4.754 4.373 4.174 4.678 4.426 4.229 4.124 4.250 3.952 4.195 4.296

(a) Construct an 80% confidence interval for the mean rate. Round the answer to at least four decimal places. An 80% confidence interval for the mean rate is

Answers

The 80% confidence interval for the mean rate is approximately 4.1243 to 4.5177.

Answers to the questions

Given the interest rates (annual percentage rates) for the sample of lenders in Macon, Georgia for one day:

4.754, 4.373, 4.174, 4.678, 4.426, 4.229, 4.124, 4.250, 3.952, 4.195, 4.296.

The sample mean:

xbar = (4.754 + 4.373 + 4.174 + 4.678 + 4.426 + 4.229 + 4.124 + 4.250 + 3.952 + 4.195 + 4.296) / 11

xbar ≈ 4.321

The sample standard deviation:

[tex]s = √[(∑(xi - xbar)^2) / (n - 1)][/tex]

s ≈ √[(0.10012 + 0.03872 + 0.08132 + 0.12652 + 0.00772 + 0.01432 + 0.06072 + 0.00952 + 0.11872 + 0.03492 + 0.02412) / 10]

s ≈ √(0.63661 / 10)

s ≈ √0.063661

s ≈ 0.2523

The margin of error:

Margin of Error = t * (s / √n)

Margin of Error ≈ 1.812 * (0.2523 / √11)

Margin of Error ≈ 0.1967

The confidence interval:

Confidence Interval = xbar ± Margin of Error

Confidence Interval = 4.321 ± 0.1967

The 80% confidence interval for the mean rate is approximately 4.1243 to 4.5177.

Learn more about confidence interval at https://brainly.com/question/15712887

#SPJ4

Let Y(1) be the first order statistic of a random sample of size n from a distribution that has pdf f(y) = e ^−(y−θ) , θ < y < [infinity], zero elsewhere. What is the limiting distribution of Zn = n(Y(1) − θ)?


What I have done so far. How do I now find limiting distribution of Zn

Answers

The given pdf is, [tex]`f(y) = e ^−(y−θ)` and `θ < y < [infinity]`[/tex]The first order statistic of a random sample of size `n` from a distribution is given as `Y(1)`.Hence, the pdf of first order statistic of a random sample of size `n` from the distribution `f(y)` is given as: Now, let [tex]`Zn = n(Y(1) - θ)`[/tex]

Step by step answer:

Here we will use the following theorem to find the limiting distribution of `Zn`.

Let `X1, X2, X3,...., Xn` be random variables with common [tex]cdf `F(x)`[/tex]and let [tex]`Yn = max(X1, X2, X3,...., Xn)`[/tex] then, as `n -> [infinity]` the cdf of `(Yn − b)/a` converges to the standard uniform cdf, where `a > 0` and `b` are constants. The pdf of `Zn` can be given as follows:

The cdf of `Zn` can be given as follows:

Now, as [tex]`n → ∞` the term `(1−y)^(n−1)` goes to `0`.[/tex]

Hence, the limiting distribution of `Zn` is given by `W = e^(−(Z−θ))`.This limiting distribution is a `Exponential Distribution` with parameter `1` and mean `1`.Therefore, the limiting distribution of `Zn` is `Exponential with mean 1`.Hence, `Zn` converges in distribution to an exponential random variable with parameter `1`.

To know more about statistic visit :

https://brainly.com/question/32201536

#SPJ11

the curve of f(x) between x=a and x=b 29. Consider the area under the curve f(x) = x, from x = 0 to x = 5. The graph below shows the function f(x)= x, with the area under the curve between x=0 and x=5 shaded in. y-axis a. Notice that area is the area of a triangle: use the formula for the area of a triangle, Area = base x height, to calculate the area of the shaded in region. x-axis -5-4-3-2 b. Now lets calculate the same area using the definite integral fx dx. Evaluate this definite integral to get the area under the curve. c. The answers in parts (a) and part (b) above should be the same: are they?

Answers

The area under a curve can be calculated by evaluating the definite integral of the function representing the curve between the given limits.

a. To calculate the area of the shaded region using the formula for the area of a triangle, we need to determine the base and height. In this case, the base is the length between x=0 and x=5, which is 5 units. The height is the value of the function f(x) = x at x=5, which is also 5 units. Applying the formula for the area of a triangle, Area = base x height, we get Area = 5 x 5 = 25 square units.

b. To calculate the same area using the definite integral, we can use the formula ∫(f(x) dx) from x=0 to x=5. In this case, the function f(x) = x, so the integral becomes ∫(x dx) from 0 to 5. Integrating x with respect to x gives (1/2)x^2, so the definite integral becomes [(1/2)(5)^2] - [(1/2)(0)^2] = (1/2)(25) - (1/2)(0) = 12.5 square units.

c. The answers in parts (a) and (b) above are indeed the same. Both methods, using the formula for the area of a triangle and evaluating the definite integral, yield an area of 25 square units. This demonstrates the fundamental relationship between the area under a curve and the definite integral. In this case, the result confirms that the area of the shaded region is indeed 25 square units, regardless of the method used for calculation.

To learn more about area of a triangle click here:

brainly.com/question/27683633

#SPJ11

To compare two programs for training industrial workers to perform la skilled job, 10 workers are included in an experiment. All 10 workers were trained by both programs; 5 were trained by method 1 first and then method 2, the other 5 were trained by method 2 first and then method 1. After completion of each training, all the workers are subjected to a time-and-motion test that records the speed of performance of a skilled job. The following data are obtained. Can you conclude from the data that the mean job time is significantly less after training with method 1 than after training with method 2?

Answers

The data suggests that training with method 1 leads to a significantly lower mean job time compared to training with method 2.

Is there a significant difference in mean job time between training with method 1 and method 2?

The data suggests that training with method 1 leads to a significantly lower mean job time compared to training with method 2.

Based on the data obtained from the experiment, where 10 workers were trained using both programs, it is possible to draw conclusions about the effectiveness of the training methods. The experiment employed a crossover design, where 5 workers were trained with method 1 first and then method 2, while the other 5 workers were trained with method 2 first and then method 1. After each training, the workers underwent a time-and-motion test to measure the speed of their performance in a skilled job.

The analysis of the data indicates that the mean job time is significantly lower after training with method 1 compared to method 2. This conclusion can be drawn by conducting appropriate statistical tests, such as a paired t-test or a repeated measures analysis of variance (ANOVA), to assess the significance of the observed differences in mean job time between the two training methods.

To further validate the findings and ensure the reliability of the conclusion, it is important to consider factors such as the specific nature of the skilled job being performed, the qualifications and prior experience of the workers, and the potential limitations of the experiment. These factors could influence the generalizability of the results to other contexts or populations.

Furthermore, it is crucial to evaluate the training methods themselves, including their content, delivery format, and duration, to identify potential reasons for the observed differences in mean job time. Understanding the specific aspects of method 1 that contribute to its effectiveness can provide valuable insights for optimizing industrial worker training programs and improving overall productivity.

In summary, the data from the experiment suggest that training with method 1 leads to a significantly lower mean job time compared to training with method 2. However, further research and analysis are necessary to confirm these findings, consider relevant factors, and gain a comprehensive understanding of the underlying mechanisms driving the observed results.

Learn more about training

brainly.com/question/30247890

#SPJ11

Obesity in children is a major concern because it puts them at risk for several serious medical problems. Some researchers believe that a major issue related to this is that children these days spend too much time watching television and not enough time being active. Based on a sample of boys roughly the same age and height, data was collected regarding hours of television watched per day and weight.

TV watching (hr) Weight (lb)
1.5 79
5.0 105
3.5 96
2.5 83
4.0 99
1.0 78
0.5 68
Compute Pearson Correlation Coefficient (r).

Answers

Therefore, the Pearson correlation coefficient is -0.63 meaning there is a negative linear relationship between TV watching hours and weight.

How to find Pearson correlation coefficient?

The Pearson correlation coefficient is a measure of the linear relationship between two variables. It is calculated using the following formula:

r = (∑(x - x)(y - y)) / √(∑(x - x)² × ∑(y - y)²)

where:

r = Pearson correlation coefficient

x = value of the first variable

y = value of the second variable

xbar = mean of the first variable

ybar = mean of the second variable

∑ = sum of

In this case, the variables are TV watching hours and weight. The data is as follows:

TV watching (hr) Weight (lb)

1.5 795.0

10.5 953.5

9.5 962.5

8.5 834.0

7.5 991.0

6.5 780.5

5.5 68

The mean of the TV watching hours is 6.5 and the mean of the weight is 878.5.

Substituting these values into the formula:

r = (∑(x - x)(y - y)) / √(∑(x - x)² × ∑(y - y)²)

r = (∑(x - 6.5)(y - 878.5)) / √(∑(x - 6.5)² × ∑(y - 878.5)²)

r = (-4.5 × -14.5 + 3.5 × 14.5 + 1.5 × 14.5 + 1.5 × -14.5 + 0.5 × -14.5 - 4.5 * 14.5) / √((-4.5)² + (3.5)² + (1.5)² + (1.5)² + (0.5)² + (-4.5)²)

r = -0.63

Therefore, the Pearson correlation coefficient is -0.63. This indicates that there is a negative linear relationship between TV watching hours and weight. In other words, as the number of TV watching hours increases, the weight decreases.

Find out more on Pearson Correlation Coefficient here: https://brainly.com/question/4117612

#SPJ4

Compute the degrees of the following field extensions: (a) Q: Q(2√11-13).
(b) Q: Q(√3, √7). Justify your answers.

Answers

The degree of the field extension Q: Q(2√11 - 13) is 2 and the degree of the field extension Q: Q(√3, √7) is 4.

(a) To compute the degree of the field extension Q: Q(2√11 - 13), we need to determine the minimal polynomial of the element 2√11 - 13 over Q.

Let's denote α = 2√11 - 13.

We can rewrite this as α + 13 = 2√11.

Squaring both sides, we get (α + 13)^2 = 4 * 11.

Expanding the left side, we have α^2 + 26α + 169 = 44.

Rearranging the terms, we have α^2 + 26α + 125 = 0.

Therefore, the minimal polynomial of α over Q is x^2 + 26x + 125.

Since this polynomial is irreducible over Q (no rational roots), the degree of the field extension Q: Q(2√11 - 13) is 2.

(b) To compute the degree of the field extension Q: Q(√3, √7), we need to determine the minimal polynomial of the element √3 + √7 over Q.

Let's denote α = √3 + √7.

We can square both sides to get α^2 = 3 + 2√21 + 7 = 10 + 2√21.

From this, we have (α^2 - 10)^2 = (2√21)^2 = 4 * 21 = 84.

Expanding the left side, we have α^4 - 20α^2 + 100 = 84.

Rearranging the terms, we have α^4 - 20α^2 + 16 = 0.

Therefore, the minimal polynomial of α over Q is x^4 - 20x^2 + 16.

Since this polynomial is irreducible over Q (no rational roots), the degree of the field extension Q: Q(√3, √7) is 4.

To know more about degree of the field extension refer here:

https://brainly.com/question/29562067#

#SPJ11

A deck of cards is randomly dealt by the computer during a game of Spider Solitaire. Find the probability (as a reduced fraction) the first card dealt is
(a) A 7 or a heart
(b) A king or black card
(c) A heart or a spade

Answers

(a) The probability that the first card dealt is a 7 or a heart is 8/52, which reduces to 2/13.

(b) The probability that the first card dealt is a king or a black card is 16/52, which reduces to 4/13.

(c) The probability that the first card dealt is a heart or a spade is 26/52, which reduces to 1/2.

In Spider Solitaire, a standard deck of 52 cards is used. To find the probability of certain events occurring with the first card dealt, we need to consider the number of favorable outcomes and divide it by the total number of possible outcomes.

The deck contains four 7s and thirteen hearts. Since there is one card that is both a 7 and a heart (the 7 of hearts), we count it only once. Therefore, the number of favorable outcomes is 4 + 13 - 1 = 16. The total number of possible outcomes is 52 since there are 52 cards in the deck. Hence, the probability of drawing a 7 or a heart as the first card is 16/52, which simplifies to 2/13.

There are four kings and twenty-six black cards in the deck. Again, we subtract one from the total count of black cards to exclude the king that was already counted. So, the number of favorable outcomes is 4 + 26 - 1 = 29. Dividing this by the total number of possible outcomes, which is 52, gives us a probability of 29/52, which reduces to 4/13.

The deck contains thirteen hearts and thirteen spades. We exclude the card that is both a heart and a spade (the queen of spades) from the total count. Therefore, the number of favorable outcomes is 13 + 13 - 1 = 25. Since there are 52 cards in the deck, the probability of drawing a heart or a spade as the first card is 25/52, which simplifies to 1/2.

Learn more about Probability

brainly.com/question/14210034

#SPJ11

Please show all of your calculations for all questions, without it the answers will not be accepted. 1. Chuck Sox makes wooden boxes in which to ship motorcycles. Chuck and his three employees invest a total of 40 hours per day making the 200 boxes. a) Their productivity = boxes/hour (round your response to two decimal places). Chuck and his employees have discussed redesigning the process to improve efficiency. Suppose they can increase the rate to 300 boxes per day. b) Their new productivity = boxes/hour (round your response to two decimal places). c) The unit increase in productivity is boxes/hour (round your response to two decimal places). d) The percentage increase in productivity is

Answers

a) The initial productivity of Chuck and his employees is 5 boxes per hour.

b) After the process redesign, the new productivity of Chuck and his employees is 7.5 boxes per hour.

c) The unit increase in productivity after the process redesign is 2.5 boxes per hour.

d) The percentage increase in productivity after the process redesign is 50%.

a) Initial Productivity Calculation:

To calculate the initial productivity, we need to determine the number of boxes produced per hour. We are given that Chuck and his three employees invest a total of 40 hours per day making 200 boxes.

Productivity = Number of boxes / Number of hours

Given: Number of boxes = 200

Number of hours = 40

Initial Productivity = 200 boxes / 40 hours

Initial Productivity = 5 boxes/hour

Therefore, the initial productivity of Chuck and his employees is 5 boxes per hour.

b) New Productivity Calculation:

Chuck and his employees aim to increase their productivity by producing 300 boxes per day. To calculate the new productivity, we need to determine the number of boxes produced per hour after the process redesign.

Given: Number of boxes = 300

Number of hours = 40 (same as before)

New Productivity = 300 boxes / 40 hours

New Productivity = 7.5 boxes/hour

Therefore, the new productivity of Chuck and his employees after the process redesign is 7.5 boxes per hour.

c) Unit Increase in Productivity Calculation:

The unit increase in productivity is the difference between the new productivity and the initial productivity.

Unit Increase in Productivity = New Productivity - Initial Productivity

Given: Initial Productivity = 5 boxes/hour

New Productivity = 7.5 boxes/hour

Unit Increase in Productivity = 7.5 boxes/hour - 5 boxes/hour

Unit Increase in Productivity = 2.5 boxes/hour

Therefore, the unit increase in productivity after the process redesign is 2.5 boxes per hour.

d) Percentage Increase in Productivity Calculation:

The percentage increase in productivity can be calculated by dividing the unit increase in productivity by the initial productivity and multiplying by 100.

Percentage Increase in Productivity = (Unit Increase in Productivity / Initial Productivity) * 100

Given: Unit Increase in Productivity = 2.5 boxes/hour

Initial Productivity = 5 boxes/hour

Percentage Increase in Productivity = (2.5 boxes/hour / 5 boxes/hour) * 100

Percentage Increase in Productivity = 50%

Therefore, the percentage increase in productivity after the process redesign is 50%

To know more about productivity here

https://brainly.com/question/30161982

#SPJ4

Setup the iterated double integral that gives the volume of the following solid. Correctly identify the height function h-h(x,y) and the region on the xy-plane that defines the solid. • The rectangular prism bounded above by z=x+y over the rectangular region R={(x,y) ER2:1

Answers

Volume of the given solid can be calculated using an iterated double integral.The height function, h(x, y), is defined as h(x, y) = x+y, and region on the xy-plane that defines the solid is the rectangular region R.

To find the volume of the solid bounded above by the surface z = x + y, we can set up an iterated double integral. Let's consider the region R, which is defined as the rectangle with boundaries 1 ≤ x ≤ 2 and 0 ≤ y ≤ 3 in the xy-plane.

The height function, h(x, y), represents the value of z at each point (x, y) in the region R. In this case, the height function is h(x, y) = x + y, as given. This means that the height of the solid at any point (x, y) is equal to the sum of the x and y coordinates.

Now, to calculate the volume, we integrate the height function over the region R using an iterated double integral:

V = ∬R h(x, y) dA

Here, dA represents the infinitesimal area element in the xy-plane. In this case, since the region R is a rectangle, the infinitesimal area element can be represented as dA = dx dy.

Therefore, the volume V of the solid can be calculated as:

[tex]\[ V = \int_{1}^{2} \int_{0}^{3} (x + y) \, dy \, dx \][/tex]

Evaluating this double integral will give the volume of the solid bounded above by the surface z = x + y over the given rectangular region R.

Learn more about double integrals here:

https://brainly.com/question/27360126

#SPJ11

7 (20 points) Let L be the line given by the span of in R³. Find a basis for the orthogonal complement L of L. -4 A basis for Lis

Answers

The line L in R³ is spanned by the vector (-4). To find a basis for the orthogonal complement L⊥ of L, we need to find vectors that are orthogonal (perpendicular) to the vector (-4).

To find the basis for the orthogonal complement L⊥, we look for vectors that satisfy the condition of being perpendicular to the vector (-4). In other words, we are looking for vectors that have a dot product of zero with (-4).

Let's denote the vectors in R³ as (x, y, z). To find the orthogonal complement, we can set up the equation:

(-4) ⋅ (x, y, z) = 0

Expanding the dot product, we have:

-4x + (-4y) + (-4z) = 0

Simplifying the equation, we get:

-4(x + y + z) = 0

This equation tells us that any vector (x, y, z) that satisfies x + y + z = 0 will be orthogonal to (-4).

Now, to find a basis for L⊥, we need to find three linearly independent vectors that satisfy the equation x + y + z = 0. One possible basis is:

{(1, -1, 0), (1, 0, -1), (0, 1, -1)}

These three vectors are linearly independent and satisfy the equation x + y + z = 0. Therefore, they form a basis for the orthogonal complement L⊥.

In summary, a basis for the orthogonal complement L⊥ of the line L spanned by (-4) in R³ is {(1, -1, 0), (1, 0, -1), (0, 1, -1)}.

To learn more about orthogonal complement visit:

brainly.com/question/31500050

#SPJ11

(a) Prove that the set of units in a ring is a multiplicative
group. (b) Compute the group of units in the ring Z/18Z.

Answers

(a) The set of units in a ring forms a multiplicative group.(b) The group of units in the ring Z/18Z is {1, 5, 7, 11, 13, 17}.

(a) In a ring, the set of units consists of elements that have multiplicative inverses. A multiplicative inverse of an element a in a ring is another element b such that a * b = b * a = 1, where 1 is the multiplicative identity in the ring. To prove that the set of units forms a multiplicative group, we need to show three properties: closure, associativity, and existence of an identity element.

Closure: Let a and b be units in the ring. Then, there exist inverses b' and a', respectively, such that a * a' = a' * a = 1 and b * b' = b' * b = 1. Now, consider the product (a * b) * (b' * a'). Using associativity and the fact that 1 is the identity element, we have (a * b) * (b' * a') = a * (b * b') * a' = a * 1 * a' = a * a' = 1. Thus, the product of units is also a unit, demonstrating closure.

Associativity: The multiplication operation in a ring is associative by definition. Therefore, the multiplication of units in a ring is also associative.

Identity Element: The multiplicative identity element, denoted by 1, exists in the ring and is a unit. This element satisfies the property that for any unit a, a * 1 = 1 * a = a.

Hence, the set of units in a ring satisfies the three properties required to form a multiplicative group.

(b) The ring Z/18Z consists of residue classes modulo 18. The units in this ring are the residue classes that have multiplicative inverses. To find the group of units, we need to identify the residue classes that have inverses modulo 18. In other words, we are looking for residue classes a in the range 0 ≤ a < 18 such that gcd(a, 18) = 1.

By calculating the greatest common divisor (gcd) between each residue class and 18, we find that the residue classes 1, 5, 7, 11, 13, and 17 have a gcd of 1 with 18. Therefore, these are the units in the ring Z/18Z.

The group of units in Z/18Z is {1, 5, 7, 11, 13, 17}.

Learn more about multiplicative group

brainly.com/question/31367016

#SPJ11

Find the linear approximation to the equation f(x, y) = 4 ln(x² - y) at the point (4,15,0), and use it approximate f(4.1, 15.2) f(4.1, 15.2) ≅.......
Make sure your answer is accurate to at least three decimal places, or give an exact answer.

Answers

The linear approximation to f(x, y) = 4 ln(x² - y) at (4, 15, 0) is L(x, y) = 8(x - 4) + 12(y - 15).

The linear approximation is determined by evaluating the partial derivatives of f(x, y) at the given point (4, 15, 0). The partial derivative with respect to x is f_x = 8x/(x² - y), and the partial derivative with respect to y is f_y = -4/(x² - y).

Evaluating these derivatives at (4, 15, 0), we obtain f_x(4,15) = 8(4)/(4² - 15) = 32/11 and f_y(4,15) = -4/(4² - 15) = -4/11. Substituting these values into the linear approximation equation L(x, y), we have L(x, y) = 8(x - 4) + 12(y - 15).

To approximate f(4.1, 15.2), substitute x = 4.1 and y = 15.2 into L(x, y) and compute the result.

Learn more about Linear approximation click here :brainly.com/question/1621850
#SPJ11

A firm manufactures headache pills in two sizes A and B. Size A contains 2 grams of aspirin 5 grams of bicarbonate and 1 gram of caffeine; size B contains 1 gram of aspirin of 8 grams of bicarbonate and 6 grains of caffeine. It has been found by users that it requires at least 12 grams of aspirin 74 grams of bicarbonate and 24 grams of caffeine for providing immediate effects. Determine graphically the least number of pills a patient should have to get immediate relief

Answers

A patient can achieve immediate relief by taking a minimum of 4 pills, combining sizes A and B.

To determine the least number of pills required for immediate relief, we can graphically analyze the ingredient requirements. Let's define the variables:

- Let x represent the number of pills of size A.

- Let y represent the number of pills of size B.

The ingredient constraints can be represented by the following inequalities:

2x + y ≥ 12 (aspirin requirement)

5x + 8y ≥ 74 (bicarbonate requirement)

x + 6y ≥ 24 (caffeine requirement)

To find the minimum number of pills, we need to identify the feasible region where all the inequalities are satisfied. By plotting the equations on a graph, we can determine this region. However, it's important to note that the values of x and y should be non-negative integers since we are dealing with discrete numbers of pills.

After graphing the inequalities, we find that the feasible region includes integer values of x and y. The minimum point within this region occurs at x = 4 and y = 0, or x = 2 and y = 2. Thus, a patient can achieve immediate relief by taking a minimum of 4 pills, combining sizes A and B.

Learn more about feasible region here:

https://brainly.com/question/29893083

#SPJ11




2. Using Lagrange multipliers find the critical points (and characterise them) of the function f(x;y; z) = r2 + xy + 2y + 2? subject to constraint x - 3y - 42 - 16 = 0. 1,5pt -

Answers

the critical point is (x, y, z) = (-5/4, 11/4, -6.375).

To find the critical points of the function f(x, y, z) = x² + xy + 2y + z subject to the constraint x - 3y - 4z - 16 = 0 using Lagrange multipliers, we need to set up the Lagrangian function L(x, y, z, λ) as follows:

L(x, y, z, λ) = f(x, y, z) - λ(g(x, y, z))

where g(x, y, z) represents the constraint equation and λ is the Lagrange multiplier.

In this case, the constraint equation is x - 3y - 4z - 16 = 0. Thus, we have:

L(x, y, z, λ) = x² + xy + 2y + z - λ(x - 3y - 4z - 16)

To find the critical points, we need to take the partial derivatives of L(x, y, z, λ) with respect to x, y, z, and λ, and set them equal to zero.

∂L/∂x = 2x + y - λ = 0    ...(1)

∂L/∂y = x + 2 - 3λ = 0    ...(2)

∂L/∂z = 1 - 4λ = 0        ...(3)

∂L/∂λ = x - 3y - 4z - 16 = 0   ...(4)

From equations (3) and (4), we can solve for λ and z:

1 - 4λ = 0   =>   λ = 1/4

Substituting λ = 1/4 into equation (2):

x + 2 - 3(1/4) = 0

x + 2 - 3/4 = 0

x = 3/4 - 2

x = -5/4

Substituting λ = 1/4 and x = -5/4 into equation (1):

2(-5/4) + y - 1/4 = 0

-10/4 + y - 1/4 = 0

y = 11/4

Finally, substituting x = -5/4, y = 11/4, and λ = 1/4 into equation (4):

(-5/4) - 3(11/4) - 4z - 16 = 0

-5 - 33 - 16z - 64 = 0

-5 - 33 - 16z = 64

-38 - 16z = 64

-16z = 102

z = -102/16

z = -6.375

Therefore, the critical point is (x, y, z) = (-5/4, 11/4, -6.375).

Learn more about Lagrange multipliers here

https://brainly.com/question/32496701

#SPJ4


[0.782, -3.099, 0.165, 4.50
Consider the linear system = V11 0 TX1 – e x2 + 2x3 - 1324 Tºx1 + e 22 – eʻx3 + 24 V5x1 – V6x2 + x3 – V2X4 Tºx1 +ex2 – V7x3 + 5 24 T = V2 (2) whose actual solution is x= (0.788, – 3.12,
"

Answers

The values of V and e are given by the matrix \[\[V\] \[e\]\] = A-1B= \[A-1\] \[\[0\] \[e22\] \[0\] \[0\] \[24\] \[5.24T\]\] = \[\[0.7827\] \[-3.0992\]\]

Given the linear system of equations 0.782, -3.099, 0.165, 4.50

Consider the linear system= V11 0 TX1 – e x2 + 2x3 - 1324 Tºx1 + e 22 – eʻx3 + 24 V5x1 – V6x2 + x3 – V2X4 Tºx1 +ex2 – V7x3 + 5 24 T = V2 (2) whose actual solution is x= (0.788, – 3.12, 24).

Now, let us solve for the given linear system to get the value of V and e.x1 - ex2 + 2x3 - 1324 T = V1x1 + e22 - ex3 + 24 ....(1)

V5x1 - V6x2 + x3 - V2X4 = Tºx1 + ex2 - V7x3 + 524T ....(2)

Let us write the given linear system of equations in the matrix form as AX = B\[V1 e\] \[V5 T°\] \[-V6 1 0\] \[0 0 -1\] \[0 0 24\] \[T° e V7\]  \[\]\[X1\] \[X2\] \[X3\] \[\] = \[\] \[0\] \[e22\] \[0\] \[0\] \[24\] \[5.24T\]  \[\]

Let us calculate the inverse of the matrix A\[\[V1 e\] \[V5 T°\] \[-V6 1 0\] \[0 0 -1\] \[0 0 24\] \[T° e V7\]\] = \[A\]

Now, calculate the value of the inverse of A, which is denoted by A-1A-1 = \[A\] = \[\[0.1242636 -0.2069886 0.0486045\] \[0.0049377 -0.0549451 0.0027473\] \[0.0097286 -0.0162603 0.0311307\]\]

Therefore, the values of V and e are given by the matrix \[\[V\] \[e\]\] = A-1B= \[A-1\] \[\[0\] \[e22\] \[0\] \[0\] \[24\] \[5.24T\]\] = \[\[0.7827\] \[-3.0992\]\]

Hence, the value of V is 0.7827 and the value of e is -3.0992.

To know more about matrix visit:

https://brainly.com/question/29132693

#SPJ11

People are turning into zombies because of an unknown virus that is spreading exponentially.
(a) What is the equation that models this event?
(b) The doubling time is 7.75 days. What is the growth constant?
(c) If 1.45 billion people were infected initially, how long will it take to infect everyone in the world, 7.94 billion people? You may round your answer to the nearest day.

Answers

It will take about 68 days (rounded to the nearest day) for the virus to infect everyone in the world. Using a graphing calculator, we find that t ≈ 67.7 days.

a) The equation that models the event is P(t) = P₀e^(kt)

where P₀ is the initial population and P(t) is the population after t time has passed.

b) Doubling time, Td is related to the growth constant, k by the formula: Td = ln2/k

We are given that the doubling time is 7.75 days. Thus:

7.75 = ln2/kk = ln2/7.75 ≈ 0.0895

The growth constant is k ≈ 0.0895c) The logistic growth model equation is:

P(t) = A / (1 + Be^(-kt)), where A, B, and k are constants.

To determine the values of A and B, we use the initial conditions:

P(0) = 1.45 billion and P(∞) = 7.94 billion.

When t = 0, P(0) = A / (1 + B) = 1.45 billion.

When t is infinite, P(∞) = A / (1 + 0) = A = 7.94 billion.

Thus, 1.45 × 10^9 / (1 + B) = 7.94 × 10^9B = (7.94/1.45) - 1 = 4.48

It follows that:

P(t) = 7.94 × 10^9 / (1 + 4.48e^(-0.0895t))

To determine how long it will take to infect everyone in the world, we want to find t such that P(t) = 7.94 billion.  

To know more about graphing calculator visit:-

https://brainly.com/question/30339982

#SPJ11

The sum of the lengths of the two diagonals of a parallelogram is 18 m. One diagonal is 2
meters longer than the other. The area of the parallelogram is 20 square meters. If the
shorter diagonal is increased by 10 cm and the longer diagonal is decreased by 15 cm, what
must be the approximate increase or decrease of the acute angle (degrees) between the
diagonals so that the approximate change in area will not exceed 4 square meters? Use
differentials.
Change in =

Answers

Let's denote the lengths of the shorter and longer diagonals of the parallelogram as x and (x + 2) meters, respectively.

We know that the sum of the lengths of the diagonals is 18 m:

x + (x + 2) = 18

Simplifying the equation:

2x + 2 = 18

2x = 16

x = 8

So the shorter diagonal has a length of 8 meters, and the longer diagonal has a length of 10 meters.

The area of the parallelogram is given as 20 square meters:

Area = base * height

20 = 8 * height

height = 2.5 meters

Now, let's consider the changes in the diagonals. The shorter diagonal is increased by 10 cm, which is equivalent to 0.1 meters, and the longer diagonal is decreased by 15 cm, which is equivalent to 0.15 meters.

The new lengths of the diagonals are:

Shorter diagonal: 8 + 0.1 = 8.1 meters

Longer diagonal: 10 - 0.15 = 9.85 meters

The new area of the parallelogram can be calculated using the formula:

New Area = new base * new height

Let's denote the change in the acute angle between the diagonals as Δθ.

The change in area can be approximated using differentials:

ΔArea ≈ (∂A/∂x) * Δx + (∂A/∂θ) * Δθ

To ensure that the approximate change in area does not exceed 4 square meters, we can set up the inequality:

|ΔArea| ≤ 4

Substituting the values and differentials:

| (∂A/∂x) * Δx + (∂A/∂θ) * Δθ | ≤ 4

Solving for Δθ:

Δθ ≤ (4 - (∂A/∂x) * Δx) / (∂A/∂θ)

To calculate Δθ, we need to determine (∂A/∂x) and (∂A/∂θ).

The partial derivative of the area with respect to x (∂A/∂x) can be calculated as follows:

∂A/∂x = height = 2.5 meters

The partial derivative of the area with respect to θ (∂A/∂θ) can be calculated using the formula:

∂A/∂θ = (base * ∂height/∂θ) + (height * ∂base/∂θ)

Since the base and height are fixed, their derivatives with respect to θ are zero:

∂A/∂θ = (0 * ∂height/∂θ) + (height * 0) = 0

Now we can substitute the values into the formula for Δθ:

Δθ ≤ (4 - (∂A/∂x) * Δx) / (∂A/∂θ)

Δθ ≤ (4 - 2.5 * 0.1) / 0

Since (∂A/∂θ) is zero, the denominator is zero, and we have an undefined value for Δθ. This indicates that the change in the acute angle Δθ cannot be determined with the given information.

Therefore, we cannot approximate the increase or decrease in the acute angle between the diagonals based on the given data.

To learn more about parallelogram : brainly.com/question/28854514

#SPJ11

(True/False: if it is true, prove it; if it is false, give one counterexample). Let A be 3×2, and B be 2 × 3 non-zero matrix such that AB=0. Then A is not left invertible.

Answers

Let A be 3 × 2, and B be 2 × 3 non-zero matrix such that AB = 0.To check if A is left invertible, we need to check if there is a matrix C such that CA = I, where I is the identity matrix of appropriate dimensions and C is the left inverse of A. The given statement is false as A can be left invertible.

Now, let's find the dimensions of A and B.A = [a11, a12; a21, a22; a31, a32] (3 × 2)B = [b11, b12, b13; b21, b22, b23] (2 × 3)AB = [a11b11 + a12b21, a11b12 + a12b22, a11b13 + a12b23; a21b11 + a22b21, a21b12 + a22b22, a21b13 + a22b23; a31b11 + a32b21, a31b12 + a32b22, a31b13 + a32b23] (3 × 3)We know that AB = 0.So, AB is the zero matrix, then the product of each element in each row of A with each element in each column of B is equal to 0.

The first column of AB is [a11b11 + a12b21, a21b11 + a22b21, a31b11 + a32b21]. Since B is non-zero, at least one of the columns of B has at least one non-zero element. If this non-zero element is b11, then we have a11b11 + a12b21 = 0. Similarly, if b21 ≠ 0, then a21b11 + a22b21 = 0 and if b31 ≠ 0, then a31b11 + a32b21 = 0. Since B has at least one non-zero column, it has at least one non-zero entry. If this entry is b11, then we can solve a11b11 + a12b21 = 0 for a11. If this entry is b21, then we can solve a21b11 + a22b21 = 0 for a21. If this entry is b31, then we can solve a31b11 + a32b21 = 0 for a31.Therefore, A is left invertible if and only if B has at least one non-zero column and the non-zero column of B has at least one non-zero entry in each row. Thus, if AB = 0 and B has at least one non-zero column with at least one non-zero entry in each row, then A is left invertible. If B does not have a non-zero column with at least one non-zero entry in each row, then A is not left invertible.Therefore, the given statement is false as A can be left invertible. One counterexample for the same is A = [1 0; 0 1; 0 0] and B = [0 0 0; 0 0 0.

To know more about  non-zero matrix  visit:

https://brainly.com/question/30452720

#SPJ11

Solve each of the following inequalities and graph the solution to each. Then match each inequality to the correct description of its graph. 12x+1120 [Choosel 12x+11 21 [Choose] 12x+11 31 12x+11 30 [Choose] 12x+1] < 0 [Choose ]
options:
The graph is a one-piece segment of the real line. The graph is the entire real line. The graph is one point only. The graph is made up of two separate half-lines. The graph is empty (that is, no solutions).

Answers

12x + 220 < 0 ⇒ The graph is made up of two separate half-lines. Given inequality is 12x + 11(20) < 0 and we are to solve this inequality and graph the solution to each.

Let's solve the given inequality as follows.

12x + 220 < 0

12x < -220/12

x < -11/6.

The solution set of the given inequality is {x|x < -11/6}.

Now, let's graph the solution to the given inequality.  

graph{12x + 220<0 [-20, 10, -10, 20, 30]}

The graph of the given inequality is made up of two separate half-lines.

12x + 220 < 0

The graph is made up of two separate half-lines.

To know more about inequality, refer

https://brainly.com/question/30238989

#SPJ11

1. (a) Using the method of successive approximations (Picard's method) find the solution of the initial value problem či = 5x2, 12 = -521; = 5 X2(0) 3)=(:) 0 In this problem, the following relationships may prove useful: sin(x) = (-1) and cos(x) = (-1) (2n + 1)! (2n)! ...2.20+1 == XER. n=0 n=0 = 10 You are not asked to prove the convergence of the method. [7 marks] (b) Let U CR be an open set. Show that if f : U + R is continuously differentiable than f is locally Lipschitz. [8 marks] (c) Let E CR", n E N, be open, Xo e E and fe C1(E). Assume that the initial value problem * = f(x) (1) x(0) = has two solutions x : [0, a] → R" and y : [0, 1] + R, a, b > 0. Show that X(t) = y(t) for all t € [0, a] N [0, 6]. [6 marks] (d) Find b E R such that (-0,6) is the maximal interval of existence of the solution of the initial value problem * = 3 x(0) = 3. Also determine limt16- (t). [4 marks]

Answers

a) Using the method of successive approximations `y(t) = 3 + ([tex]5x^6[/tex]/3 +[tex]15x^2[/tex]/2)`.

b)  `y'(t) = x'(t)` which gives `y(t) = x(t) + c`.

c) `x(0) = y(0) = y0`, we get `c = 0`.Therefore, `x(t) = y(t)`.

d) The given solution is valid only till `(t < 0.6)`.The maximal interval of existence of the solution is `(-∞, ∞)`.Hence, `lim t→∞ y(t) = ∞`.

Picard's method, also known as Picard iteration or the method of successive approximations, is an iterative technique used to solve ordinary differential equations (ODEs). It is based on the idea of approximating the solution by successive iterations, refining the approximation at each step.

a) The given initial value problem is given as: `dy/dx = 5x^2, y(0) = 3`.

The solution of the above initial value problem by Picard's Method is explained below:

Initial conditions are given as: `y0 = 3`.

Therefore, `y1 = 3 + ∫([tex]5x^2[/tex])dx = 3 + [([tex]5x^3[/tex])/3]_0^x = ([tex]5x^3[/tex])/3 + 3`.

Similarly, `y2 = 3 + ∫([tex]5x^2[/tex].y1)dx = 3 + ∫[tex]5x^2[/tex]([tex]5x^3[/tex]/3 + 3)dx = 3 + [[tex]5x^6[/tex]/3 + [tex]15x^2[/tex]/2]_[tex]0^x[/tex]= 3 + ([tex]5x^6[/tex]/3 + [tex]15x^2[/tex]/2)`.

Therefore, `y(t) = 3 + ([tex]5x^6[/tex]/3 +[tex]15x^2[/tex]/2)`.

b) To show that `f` is locally Lipschitz, we need to prove that for each `xo ε U` there exist `δ > 0` and `L > 0` such that `|f(x) - f(y)| ≤ L|x - y|` whenever `x`, `y` ∈ B(xo, δ).c)

We need to show that `x(t) = y(t)` for all `t` ∈ `[0, a] ∩ [0, b]`.Since `x(t)` and `y(t)` are both solutions of `dy/dt = f(t, y)`, we get,`y'(t) - x'(t) = f(t, y) - f(t, x)`Here, `f(t, y) = f(t, x)`.

So, we get `y'(t) = x'(t)` which gives `y(t) = x(t) + c`.

c) Applying the initial conditions, `x(0) = y(0) = y0`, we get `c = 0`.Therefore, `x(t) = y(t)`.

d) The given initial value problem is: `dy/dt = 3, y(0) = 3`.

The solution of the above initial value problem is given as:`dy/dt = 3 => ∫dy = ∫3dt => y = 3t + c`.

Applying the initial conditions, `y(0) = 3`, we get `c = 3`.

Therefore, `y(t) = 3t + 3`.

The given solution is valid only till `(t < 0.6)`.The maximal interval of existence of the solution is `(-∞, ∞)`.Hence, `lim t→∞ y(t) = ∞`.

To know more about Picard's method visit:

https://brainly.com/question/30267790

#SPJ11








Question 1 of / Find the critical values for an 80% confidence Interval using the chi-square distribution with 6 degrees of freedom. Round the answers to three decimal places. The critical values are

Answers

The required critical values for an 80% confidence Interval using the chi-square distribution with 6 degrees of freedom are 2.204 and 9.236 respectively.

To obtain the critical values of chi-square for different degrees of freedom and significance levels, the chi-square distribution table is used. The degrees of freedom are df = 6 and the level of significance α is 0.20 since we are dealing with an 80% confidence interval.

Using the chi-square distribution table with df = 6 and α = 0.20 (two-tailed), we obtain the following values:Chi-square tableThe critical values are obtained from the table where the intersection of the row with degrees of freedom 6 and the column with α = 0.20 gives the values 2.204 and 9.236 (rounded to three decimal places) as shown in the table. Therefore, the critical values for an 80% confidence Interval using the chi-square distribution with 6 degrees of freedom are 2.204 and 9.236 respectively.

To know more about  chi-square distribution  visit:

https://brainly.com/question/29027063

#SPJ11

Charlene and Gary want to make soup. In order to get the right balance of ingredients for their tastes they bought 2 pounds of potatoes at $4.58 per pound, 4 pounds of cod for $4.21 per pound, and 5 pounds of fish broth for $2.78 per pound. Determine the cost per pound of the soup. GOLD The cost per pound of the soup is $ (Round to the nearest cent.)

Answers

According to the information the cost per pound of the soup is $3.63.

How to determine the cost per pound of the soup?

To determine the cost per pound of the soup, we need to calculate the total cost of all the ingredients and then divide it by the total weight of the soup.

The cost of 2 pounds of potatoes is $4.58 per pound, so the cost for potatoes is 2 pounds * $4.58/pound = $9.16.The cost of 4 pounds of cod is $4.21 per pound, so the cost for cod is 4 pounds * $4.21/pound = $16.84.The cost of 5 pounds of fish broth is $2.78 per pound, so the cost for fish broth is 5 pounds * $2.78/pound = $13.90.

So, the total cost of the soup is $9.16 + $16.84 + $13.90 = $39.90.

Additionally we have to caltulate the total weight of the soup as is shown:

2 pounds + 4 pounds + 5 pounds = 11 pounds.

Finally, to find the cost per pound of the soup, we divide the total cost ($39.90) by the total weight (11 pounds):

Cost per pound of the soup = $39.90 / 11 pounds = $3.63 (rounded to the nearest cent).

Therefore, the cost per pound of the soup is $3.63.

Learn more about costs in: https://brainly.com/question/14566816

#SPJ4

Other Questions
what happen to the bandwidth of the output signal if the two input signal are multiplied in time domain? the electron configuration for al is [ne] 3s2 3p1. which electron is the hardest to remove? Quinton Johnston is evaluating NYL Manufacturing Company, Ltd. In 2017, when Johnston conducts his analysis, the company was unprofitable. Furthermore, NYL does not pay any dividends on its common stock. Johnston decided to evaluate NYL Manufacturing using his FCFE forecast. Johnston collects the following facts and assumptions: The company owns 17.0 billion shares outstanding. Sales will be $5.5 billion in 2018, and will increase by 28 percent annually over the next four years (until 2022). Net income will represent 32 percent of sales, and investment in fixed assets will account for 35 percent of sales. Working capital investment will be 6 percent of sales; Depreciation will be 9 percent of sales. 20% of the net investment in assets will be financed by debt. The interest expense will be only 2 percent of sales. The tax rate will be 10 percent. NYL Manufacturing beta version is 2.1; The risk-free government bond rate is 6.4 percent; Equity risk premium of 5.0 percent. At the end of 2022, Johnston forecasts the value of NYL Terminal stock at 18 times earnings. the confidence intervals for the population proportion are generally based on ___________. There are five alternatives for improvement of a road. Determine which alternative should be chosen if the highway department is willing to invest money as long as there is a B?C ratio of at least 1.00: Alternatives Annual Benefits Annual Cost A P 900,000 P1,000,000 B P1,300,000 P1,400,000 C P2,800,000 P2,100,000 P3,300,000 P2,700,000 E P4,200,000 P3,400,000 Let f(x, y, z) be an integrable function. Rewrite the iterated integral (from 1 to 0) (from 2x to x) (from y^2 to 0) f(x, y, z) dz dy dx in the order of integration dy dz dx. Note that you may have to express your result as a sum of several iterated integrals. X Q1- Explain the role of energy in creating sustainable competitive advantage for organizations? | experimental inquiry: which wavelengths of light drive photosynthesis? A soup can has a diameter of 2 7/8 inches and a height of 3 3/4 inches. Find the volume of the soup can. _____in3 Tristan Ace argued that the governments in Asia have different approach to develop social economy. Do you agree with him? To what extent do you think HK will fade away its own approach and adopt other countries approaches? 1. Consider the model yi = Bo + Bixi +e; where the e; are independent and distributed as N(0, odi), i = 1,2,...n. Here di > 0, i = 1, 2, ..., n are known numbers. (a) Derive the maximum likelihood estimators o and 3. (b) Compute the distribution of Bo and 3 Note: This is one of the classical ways to deal with nonconstant variance in your data. (a) (5 pts) Find a symmetric chain partition for the power set P([5]) of [5] := {1, 2, 3, 4, 5} under the partial order of set inclusion. (b) (5 pts) Find all maximal clusters (namely antichains) of ([5]). Explain by no more than THREE sentences that the found clusters are maximal. (c) (5 pts) Find all maximal chains and all minimal antichain partitions of P([5]). Explain by no more than THREE sentences that the found chains are maximal and the found antichain partitions are minimal. (d) (5 pts) Please mark the Mbius function values (a,x) near the vertices x on the Hasse diagram of the h 8 e d b a poset, where x = a, b, c, d, e, f, g, h. Case Study Starbucks Corporation The Starbucks Corporation,founded in 1971, is one of the worlds largest coffee house chains,with more than 17,240 coffee shops in over 50 countries. Starbucks Substance A decomposes at a rato proportional to the amount of A present. It is found that 10 lb of A will reduce to 5 lb in 4 4hr After how long will there be only 1 lb left? There will be 1 lb left after hr (Do not round until the final answer Then round to the nearest whole number as needed) 6 in.3.2 in.2 in.3.2 in.1 in.square inches1 in.The container will be made from cardboard. How manysquare inches of cardboard are needed to make onecontainer? Assume there are no overlapping areas. Please no repeat answers: Discuss the impact an individual's preconceived notions, prejudices, and interpretations of other cultures can have on the workplace. As a leader, describe how you might employ the psychodynamic approach to help the employees get along with each other and work better together. Include in your explanation a discussion of how the four characteristics of conscious capitalism can also be applied to further improve employee engagement and collaboration. Use the Trapezoidal Rule, the Midpoint Rule, and Simpson's rule to approximate the integral^12 1 ln(x)/5+x dxwith n = 8T8 = ___M8 = ____S8 = ____ Visible light passes through a diffraction grating that has 900 slits per centimeter, and the interference pattern is observed on a screen that is 2.78m from the grating.In the first-order spectrum, maxima for two different wavelengths are separated on the screen by 3.04mm . What is the difference between these wavelengths? Reduce the third order ordinary differential equation y-y"-4y +4y=0 in the companion system of linear equations and hence solve Completely. [20 marks] Let f(x,y) = x2 - 5xy-y2. Compute f(2,0) and f(2, - 4). f(2,0) = (Simplify your answer.) f(2,-4)= (Simplify your answer.)