Answer:
Step-by-step explanation:
Let x represent the number of friends that Monica asked to a charity raffle ticket. If all but 4 of her friends bought a ticket, it means that only 4 of her friends did not buy the charity raffle ticket. Thus, the number of her friends that bought the charity raffle ticket is
x - 4
If each ticket costs $3 and the total amount that was raised is $18, then algebraic expression representing the number of friends that Monica asked is
3(x - 4) = 18
3x - 12 = 18
3x = 18 + 12 = 30
x = 30/3 = 10
Monica asked 10 friends
A simple random sample of 44 adults is obtained from a normally distributed population, and each person's red blood cell count (in cells per microliter) is measured. The sample mean is 5.31 and the sample standard deviation is 0.51 . Use a 0.05 significance level and the given calculator display to test the claim that the sample is from a population with a mean less than 5.4 comma which is a value often used for the upper limit of the range of normal values. What do the results suggest about the sample group?
Answer:
There is not enough evidence to support the claim that the population mean is significantly less than 5.4.
This result suggest we may be making a Type II error, where a true alternative hypothesis does not have enough evidence to be supported.
If the same outcome would have been obtained with a bigger sample size, the power of the test is bigger and there is a higher probability of rejecting the null hypothesis.
Step-by-step explanation:
This is a hypothesis test for the population mean.
The claim is that the population mean is significantly less than 5.4.
Then, the null and alternative hypothesis are:
[tex]H_0: \mu=5.4\\\\H_a:\mu< 5.4[/tex]
The significance level is 0.05.
The sample has a size n=44.
The sample mean is M=5.31.
As the standard deviation of the population is not known, we estimate it with the sample standard deviation, that has a value of s=0.51.
The estimated standard error of the mean is computed using the formula:
[tex]s_M=\dfrac{s}{\sqrt{n}}=\dfrac{0.51}{\sqrt{44}}=0.077[/tex]
Then, we can calculate the t-statistic as:
[tex]t=\dfrac{M-\mu}{s/\sqrt{n}}=\dfrac{5.31-5.4}{0.077}=\dfrac{-0.09}{0.077}=-1.171[/tex]
The degrees of freedom for this sample size are:
[tex]df=n-1=44-1=43[/tex]
This test is a left-tailed test, with 43 degrees of freedom and t=-1.171, so the P-value for this test is calculated as (using a t-table):
[tex]\text{P-value}=P(t<-1.171)=0.124[/tex]
As the P-value (0.124) is bigger than the significance level (0.05), the effect is not significant.
The null hypothesis failed to be rejected.
There is not enough evidence to support the claim that the population mean is significantly less than 5.4.
This result suggest we may be making a Type II error, where a true alternative hypothesis does not have enough evidence to be supported.
If the same outcome would have been obtained with a bigger sample size, the power of the test is bigger and there is a higher probability of rejecting the null hypothesis.
Which expression is equivalent to 3m + 1 - m? 2 + m - 1 + m 1 + m 3m - 1 3m
Answer:
2m + 1
Step-by-step explanation:
Simply combine like terms. m terms go with m terms and constants go with constants.
Answer:
2m + 1
Step-by-step explanation:
3m + 1 - m =
= 3m - m + 1
= 2m + 1
Select the correct interpretation of the probability of getting an 11 when a pair of dice is rolled. Interpret an event as significant if its probability is less than or equal to 0.05. Select one: a. Significant at .055 b. Not significant at .945 c. Not significant at .055 d. Significant at .028
Answer:
c. Not significant at .055
Step-by-step explanation:
When a pair of dice is rolled, we have 6²=36 possible outcomes. Only 2 of these outcomes have a total score of 11:
When the first dice is 5 and the second is 6.When the first dice is 6 and the second is 5.Then, we can calculate the probability of getting 11 as the quotient between the successs outcomes and the total outcomes.
Then, the probability of getting 11 is:
[tex]P=\dfrac{X}{N}=\dfrac{2}{36}=0.055[/tex]
This probability is not equal or less than 0.05, so it is not significant at 0.055.
A circle is shown. Angles 3 and 4 intersect an arc with a measure of 106 degrees. Angles 1 and 2 intersect an arc with measure 58 degrees. Is the measure of ∠1 equal to the measure of ∠2? Why?
Answer:
yes, because they intercept the same arc
Step-by-step explanation:
Answer:
yes, because they intercept the same arc
Step-by-step explanation:
Write the equations of the line with the slope=6 that passes through (4,-6)
Answer:
y=6x+18
Step-by-step explanation:
Answer:
y = 6x - 30
Step-by-step explanation:
The slope is 6.
Use the formula for the equation of a line.
y = mx + b
Where m is the slope, and b is the y-intercept.
y = 6x + b
The point is given (4, -6)
(x , y)
Put x as 4, y as -6.
-6 = 6(4) + b
-6 = 24 + b
-6 - 24 = b
-30 = b
The y-intercept is -30.
The equation of the line is y = 6x - 30.
evaluate 25.1 * 2.51 in two decimal places
Answer:
63.00
Step-by-step explanation:
25.1 × 2.51
Multiply.
= 63.001
Round to two decimal places.
63.00
Answer:
63.00
Step-by-step explanation:
when u multiply 25.1 by 25.1 you get 630.01. Then u have to move the decimal over to the left once and then u get 63.00
Which of the following is the missing side length that completes the
Pythagorean triple below?
5, 12,
Answer:
13
Step-by-step explanation:
We can find the missing side length by using the pythagorean theorem
a² + b² = c²
5² + 12² = c²
25 + 144 = c²
169 = c²
13 = c
So, 13 is the missing side length.
Dairy cows at large commercial farms often receive injections of bST (Bovine Somatotropin), a hormone used to spur milk production. Bauman et al. (Journal of Dairy Science, 1989) reported that 12 cows given bST produced an average of 28.0 kg/d of milk. Assume that the standart deviation of milk production is 2.25 kg/d.
Requried:
a. Find a 99% confidence interval for the true mean milk production.
b. If the farms want the confidence interval to be no wider than ± 1.25 kg/d, what level of confidence would they need to use?
Answer:
a) 26.33 kg/d and 29.67 kg/d
b) 94.5%
Step-by-step explanation:
a. Find a 99% confidence interval for the true mean milk production.
We have that to find our [tex]\alpha[/tex] level, that is the subtraction of 1 by the confidence interval divided by 2. So:
[tex]\alpha = \frac{1-0.99}{2} = 0.005[/tex]
Now, we have to find z in the Ztable as such z has a pvalue of [tex]1-\alpha[/tex].
So it is z with a pvalue of [tex]1-0.005 = 0.995[/tex], so [tex]z = 2.575[/tex]
Now, find the margin of error M as such
[tex]M = z*\frac{\sigma}{\sqrt{n}}[/tex]
In which [tex]\sigma[/tex] is the standard deviation of the population and n is the size of the sample.
[tex]M = 2.575*\frac{2.25}{\sqrt{12}} = 1.67[/tex]
The lower end of the interval is the sample mean subtracted by M. So it is 28 - 1.67 = 26.33 kg/d
The upper end of the interval is the sample mean added to M. So it is 28 + 1.67 = 29.67 kg/d
The 99% confidence interval for the true mean milk production is between 26.33 kg/d and 29.67 kg/d
b. If the farms want the confidence interval to be no wider than ± 1.25 kg/d, what level of confidence would they need to use?
We need to find z initially, when M = 1.25.
[tex]M = z*\frac{2.25}{\sqrt{12}} = 1.67[/tex]
[tex]1.25 = z*\frac{2.25}{\sqrt{12}} = 1.67[/tex]
[tex]2.25z = 1.25\sqrt{12}[/tex]
[tex]z = \frac{1.25\sqrt{12}}{2.25}[/tex]
[tex]z = 1.92[/tex]
When [tex]z = 1.92[/tex], it has a pvalue of 0.9725.
1 - 2*(1 - 0.9725) = 0.945
So we should use a confidence level of 94.5%.
What is the height, X, of the equilateral triangle ? (Help)
Answer:
A. 7√3 in
Step-by-step explanation:
We first have to draw out the altitude on the triangle. When we do so, we should see that we will get 2 congruent 30-60-90 triangles. From there, our h height is x and we use tan∅ to solve:
tan60° = x/7
x = 7tan60°
x = 7√3
Answer:
It's A
Step-by-step explanation:
Orchid wants to retile her bathroom floor, which has an area of 40 square feet. She is deciding between two types of custom tiles. The square tile is One-half foot by One-half foot and costs $0.45 per tile. The rectangular tile is 2 feet by One-fourth foot and costs $0.80 per tile.
Which tile should Orchid choose to minimize costs? Explain.
She should choose the square tiles because the total cost will be $8 less.
She should choose the rectangular tiles because the total cost will be $8 less.
She should choose the square tiles because the total cost will be $14 less.
She should choose the rectangular tiles because the total cost will be $14 less.
Your answer is the second option, she should choose the rectangular tiles because the total cost will be $8 less.
To find this answer we need to first find the total cost for using square tiles, and the cost for using rectangular tiles, and compare them. We can do this by finding the area of each tile individually, calculating how many tiles we would need, and multiplying this by the cost for one tile:
Square tiles:
The area of one square tile is 1/2 × 1/2 = 1/4 ft. Therefore we need 40 ÷ 1/4 = 160 tiles. If each tile costs $0.45, this means the total cost will be $0.45 × 160 = $72
Rectangular tiles:
The area of one rectangular tile is 2 × 1/4 = 2/4 = 1/2 ft. Thus we need 40 ÷ 1/2 = 80 tiles. Each tile costs $0.80, so the total cost will be 80 × $0.80 = $64.
This shows us that the rectangular tiles will be cheaper by $8.
I hope this helps! Let me know if you have any questions :)
Answer:
B
Step-by-step explanation:
E2020 : )
factorise 12x² + x - 20
━━━━━━━☆☆━━━━━━━
▹ Answer
(3x + 4) * (4x - 5)
▹ Step-by-Step Explanation
12x² + x - 20
Rewrite
12x² + 16x - 15x - 20
Factor out
4x(3x + 4) - 15x - 20
4x(3x + 4) - 5(3x + 4)
Factor
(3x + 4) * (4x - 5)
Hope this helps!
- CloutAnswers ❁
Brainliest is greatly appreciated!
━━━━━━━☆☆━━━━━━━
Find the area of the yellow region.
Round to the nearest tenth.
15 cm
15 cm
Area = [ ? ] cm2
Answer:
48.3 cm²
Step-by-step explanation:
Let A be the area of the yellow region
A= the area of the square - the area of the quarter square
A= 15²-(15²*π)/4= 48.28≈ 48.3 cm²
Simplify: |2-5|-(12 ÷4-1)^2
The value of the expression when simplified is -13
How to determine the valueIt is important to note:
PEDMAS is a mathematical acronym that representing;
P for ParenthesesE for exponentsD for divisionM for multiplicationA for additionS for subtractionAlso, we should note that absolute value of a number is the non-negative value of that number. It s the value of a number irrespective of its direction from zero.
It is denoted with the symbol '| |'
Given the expression;
|2-5|-(12 ÷4-1)^2
Solve the bracket
|-3| - (12 /3)^2
Solve further
|-3| - 4^2
Find the absolute value
3 - 4^2
Find the square
3 - 16
-13
The value is - 13
Thus, the value of the expression when simplified is -13
Learn more about PEDMAS here:
https://brainly.com/question/345677
#SPJ1
In order to determine the average price of hotel rooms in Atlanta, a sample of 64 hotels was selected. It was determined that the average price of the rooms in the sample was $112. The population standard deviation is known to be $16.
a. Which form of the hypotheses should be used to test whether or not the average room price is significantly different from $108.50?
H0:
-mu is greater than or equal to $108.50
mu is greater than $108.50
mu is less than $108.50mu is less than or equal to $108.50
mu is equal to $108.50mu is not equal to $108.50
Ha: -
-mu is greater than or equal to $108.50
mu is greater than $108.50mu is less than $108.50
mu is less than or equal to $108.50
mu is equal to $108.50mu is not equal to $108.50
b. Test to determine if whether or not the average room price is significantly different from $108.50, using an alpha level of .05.
Reject H0
or
Fail to reject H0
Answer:
Step-by-step explanation:
H0: mu is equal to $108.50
Ha: mu is not equal to $108.50
This test is a two tailed test and using the z tat formula, we can ascertain if there is a difference.
z = x-u / sd/√n
Where x is $112, u is $108.50 sd is $16 and n is 64
z = 112-108.50 / 16/√64
z = 3.5/(16/8)
z = 3.5/2
z = 1.75
To help us arrive at a conclusion, we need to find the p value using alpha id = 0.05. The p value is 0.08. Since the p value is great than 0.05, we fail to reject the null and conclude that there is not enough statistical evidence to prove that the average room price is significantly different from $108.50
Round 2826 to the nearest hundred.
Answer:
2800
Step-by-step explanation:
2826 to the nearest hundred is 2800
If you average your costs over your total production, you get the average cost, written C: C(x, y) = C(x, y) x + y . Find the average cost for the cost function C(x, y) = 200,000 + 5,700x + 4,200y − 100,000e−0.01(x + y).
Answer:
Average cost
= [200,000 + 5,700x + 4,200y − 100,000e−⁰•⁰¹⁽ˣ ⁺ ʸ⁾] ÷ (x + y)
Step-by-step explanation:
Average cost is the cost per unit of production. It is expressed mathematically as the total cost divided by the total number of units produced.
If total cost = C(x, y)
Average cost = C(x, y) ÷ (x+y)
For this question, total cost function is
C(x, y) = 200,000 + 5,700x + 4,200y − 100,000e−⁰•⁰¹⁽ˣ ⁺ ʸ⁾
The average cost is simply this total cost function divided by the total number of units produced.
Average cost
= [200,000 + 5,700x + 4,200y − 100,000e−⁰•⁰¹⁽ˣ ⁺ ʸ⁾] ÷ (x + y)
If numerical values are then provided, this can then be worked around. But as the numerical values are absent, the average cost function just remains in this its raw form.
Hope this Helps!!!
An article gave the accompanying data on ultimate load (kN) for two different types of beams. Assuming the underlying distributions are Normal, calculate and interpret a 99% Cl for the difference between the true average load for the fiberglass beams and that for the carbon beams.
Type Sample size Sample Mean Sample SD
Fiberglass grid 26 33.4 2.2
Commercial carbon 26 42.8 4.3
grid
1. Calculate and interpret a 99% Cl for true average stance duration among elderly individuals.
2. Carry out a test of hypotheses at significance level 0.05 to decide whether true average stance duration is larger among elderly individuals than younger individuals.
Answer:
The 99% confidence interval for the difference between the true average load for the fiberglass beams and that for the carbon beams is (-11.937, -6.863).
Step-by-step explanation:
We have to calculate a 99% confidence interval for the difference between the true average load for the fiberglass beams and that for the carbon beams.
The sample 1 (Fiberglass), of size n1=26 has a mean of 33.4 and a standard deviation of 2.2.
The sample 2 (Carbon), of size n2=26 has a mean of 42.8 and a standard deviation of 4.3.
The difference between sample means is Md=-9.4.
[tex]M_d=M_1-M_2=33.4-42.8=-9.4[/tex]
The estimated standard error of the difference between means is computed using the formula:
[tex]s_{M_d}=\sqrt{\dfrac{\sigma_1^2}{n_1}+\dfrac{\sigma_2^2}{n_2}}=\sqrt{\dfrac{2.2^2}{26}+\dfrac{4.3^2}{26}}\\\\\\s_{M_d}=\sqrt{0.186+0.711}=\sqrt{0.897}=0.9473[/tex]
The critical t-value for a 99% confidence interval is t=2.678.
The margin of error (MOE) can be calculated as:
[tex]MOE=t\cdot s_{M_d}=2.678 \cdot 0.9473=2.537[/tex]
Then, the lower and upper bounds of the confidence interval are:
[tex]LL=M_d-t \cdot s_{M_d} = -9.4-2.537=-11.937\\\\UL=M_d+t \cdot s_{M_d} = -9.4+2.537=-6.863[/tex]
The 99% confidence interval for the difference between the true average load for the fiberglass beams and that for the carbon beams is (-11.937, -6.863).
In this way, we can calculate the individual duration of each one and the duration time, knowing that the sample means:
The 99% confidence interval for the difference between the true average load for the fiberglass beams and that for the carbon beams is -11.937 and -6.863.
We have to calculate a 99% confidence interval for the difference between the true average load for the fiberglass beams and that for the carbon beams. The sample 1 (Fiberglass), of size n1=26 has a mean of 33.4 and a standard deviation of 2.2. The sample 2 (Carbon), of size n2=26 has a mean of 42.8 and a standard deviation of 4.3. The difference between sample means is Md=-9.4.
[tex]Sm_d= \sqrt{\frac{\sigma^2_1}{n_1} +\frac{\sigma^2_2}{n_2}} = \sqrt{(0.186)+(0.711) }= 0.9473[/tex]
The critical t-value for a 99% confidednce interval is t=2.678. The margin of error (MOE) can be calculated as:
[tex]MOE=t*8M_d = (2.678)(0.9473)= 2.537[/tex]
Then, the lower and upper bounds of the confidence interval are:
[tex]LL= M_d-t*SM_d = -9.4-2.537= -11.937\\UL= M_d+t*SM_d= -9.4+2.537= -6.863[/tex]
The 99% confidence interval for the difference between the true average load for the fiberglass beams and that for the carbon beams is (-11.937, -6.863).
See more about statistics at brainly.com/question/2289255
3.A man answers 10 maths problems, one after the other. He answers the first problem correctly and the second problem incorrectly, for each of the remaining 8 problems the probability that he answers the problem correctly equals to the ratio of the number of problems that he has already answered correctly to the total number of problems that he has already answered. What is the probability that he answers exactly 5 out of 10 problems correctly
Answer:
Probability of answering 5out of 10 correctly= 0.246
Step-by-step explanation:
Total question answered= 2
Question answered correctly= 1
Probability of answered correctly= 1/2
Probability of answered correctly= 0.5
Probability of answered incorrectly = 0.5
Probability of answering 5out of 10 correctly= 10C5(0.5)^5(0.5)^5
Probability of answering 5out of 10 correctly = 10!/5!5!(0.5)^5(0.5)^5
Probability of answering 5out of 10 correctly = 252(0.03125)(0.03125)
Probability of answering 5out of 10 correctly= 0.246
find the value of x. m<2= x + 119
Answer: x = -10
Step-by-step explanation:
see image
A) congruent sides implies congruent angles A = 64°
B) Use the Triangle Sum Theorem: 64° + 64° + B = 180° --> B = 52°
C) B and C are complimentary angles: 52° + C = 90° --> C = 38°
D) Use the Triangle Sum Theorem knowing that congruent sides implies congruent angles: 38° + 2D = 180° --> D = 71°
∠2) D and ∠2 are supplementary angles: 71° + ∠2 = 180° --> ∠2 = 109°
Solve for x:
109° = x + 119
-10 = x
Answer:
x = -10
Step-by-step explanation:
Find the measure of angle m∠2
The triangles are isosceles triangles, the base angles are equal.
The other base angle is also 64°.
Using Triangle Sum Theorem.
64 + 64 + y = 180
y = 52
The top angle is 52°.
The whole angle is 90°.
90 - 52 = 38
The second triangle has base angles equal.
Using Triangle Sum Theorem.
38 + z + z = 180
z = 71
The two base angles are 71°.
Angles on a straight line add up to 180°.
71 + m∠2 = 180
m∠2 = 109
The measure of m∠2 is 109°
Find the value of x
m∠2 = x + 119
109 = x + 119
x = 109 - 119
x = -10
Simply the expression 3.4-1/2(0.75)
Answer:
3.025
Step-by-step explanation:
3.4-1/2(0.75)
3.4-0.375
3.025
Find the range of y=3/2cos4x-1
Answer:
Range = [- 2.5, 0.5] = [ - 5/2, 1/2]
Step-by-step explanation:
Smallest value of cos α = - 1,
largest value of cos α = 1.
When cos 4x = - 1, y=3/2cos4x-1 = 3/2*(-1) - 1 = - 5/2 = - 2 1/2 = - 2.5
When cos 4x = 1, y=3/2cos4x-1 = 3/2*1 - 1 = 1/2 = 0.5
Range = [- 2.5, 0.5] = [ - 5/2, 1/2]
Factor completely 5x(x + 3) + 6(x + 3). (1 point)
Answer:
The answer is ( 5x + 6 ) ( x + 3 )Step-by-step explanation:
5x(x + 3) + 6(x + 3)
The final answer is
( 5x + 6 ) ( x + 3 )
Hope this helps you
In 1998, as an advertising campaign, the Nabisco Company announced a "1000 Chips Challenge," claiming that every 18-ounce bag of their Chips Ahoy cookies contained at least 1000 chocolate chips. Dedicated statistics students at the Air Force Academy (no kidding) purchased some randomly selected bags of cookies and counted the chocolate chips. Some of their data are given below. 1219 1214 1087 1200 1419 1121 1325 1345 1244 1258 1356 1132 1191 1270 1295 1135 Find a 95% confidence interval for the mean number of chips in a bag of Chips Ahoy Cookies.
Answer:
A 95% confidence interval for the mean number of chips in a bag of Chips Ahoy Cookies is [1187.96, 1288.44].
Step-by-step explanation:
We are given that statistics students at the Air Force Academy (no kidding) purchased some randomly selected bags of cookies and counted the chocolate chips.
Some of their data are given below; 1219, 1214, 1087, 1200, 1419, 1121, 1325, 1345, 1244, 1258, 1356, 1132, 1191, 1270, 1295, 1135.
Firstly, the pivotal quantity for finding the confidence interval for the population mean is given by;
P.Q. = [tex]\frac{\bar X-\mu}{\frac{s}{\sqrt{n} } }[/tex] ~ [tex]t_n_-_1[/tex]
where, [tex]\bar X[/tex] = sample mean number of chocolate chips = [tex]\frac{\sum X}{n}[/tex] = 1238.2
s = sample standard deviation = [tex]\sqrt{\frac{\sum (X-\bar X)^{2} }{n-1} }[/tex] = 94.3
n = sample of car drivers = 16
[tex]\mu[/tex] = population mean number of chips in a bag
Here for constructing a 95% confidence interval we have used a One-sample t-test statistics because we don't know about population standard deviation.
So, 95% confidence interval for the population mean, [tex]\mu[/tex] is ;
P(-2.131 < [tex]t_1_5[/tex] < 2.131) = 0.95 {As the critical value of t at 15 degrees of
freedom are -2.131 & 2.131 with P = 2.5%}
P(-2.131 < [tex]\frac{\bar X-\mu}{\frac{s}{\sqrt{n} } }[/tex] < 2.131) = 0.95
P( [tex]-2.131 \times {\frac{s}{\sqrt{n} } }[/tex] < [tex]{\bar X-\mu}[/tex] < [tex]2.131 \times {\frac{s}{\sqrt{n} } }[/tex] ) = 0.95
P( [tex]\bar X-2.131 \times {\frac{s}{\sqrt{n} } }[/tex] < [tex]\mu[/tex] < [tex]\bar X+2.131 \times {\frac{s}{\sqrt{n} } }[/tex] ) = 0.95
95% confidence interval for [tex]\mu[/tex] = [ [tex]\bar X-2.131 \times {\frac{s}{\sqrt{n} } }[/tex] , [tex]\bar X+2.131 \times {\frac{s}{\sqrt{n} } }[/tex] ]
= [ [tex]1238.2-2.131 \times {\frac{94.3}{\sqrt{16} } }[/tex] , [tex]1238.2+2.131 \times {\frac{94.3}{\sqrt{16} } }[/tex] ]
= [1187.96, 1288.44]
Therefore, a 95% confidence interval for the mean number of chips in a bag of Chips Ahoy Cookies is [1187.96, 1288.44].
I’m Confused On The Question
The volume of a rectangular prism is given by the formula V = lwh, where l is the length of the prism, w is the width, and h is the height. Suppose a box in the shape of a rectangular prism has length (2a + 11), width (5a – 12), and height (a + 6). Which expression represents the volume of the box?
Answer:
Volume = 10a³ + 91a² + 54a - 792
Step-by-step explanation:
In the absence of answer choices, let's find the expression for the volume.
Given: Volume = length×width×height
V = lwh
length =(2a + 11)
width =(5a – 12)
height= (a + 6)
V = (2a + 11)(5a – 12) (a + 6)
Expand the first two brackets using distributive property
V = (10a² -24a +55a - 132)(a + 6)
Collect like terms
V = (10a² + 31a -132)(a + 6)
Expand the two brackets using distributive property
V = 10a³ + 31a² - 132a + 60a² + 186a - 792
Collect like terms
V = 10a³ + 91a² + 54a - 792
The expression that represents the volume of the box = 10a³ + 91a² + 54a - 792
Answer:
Volume = 10a³ + 91a² + 54a - 792
Step-by-step explanation:
Find the solution of the given initial value problem. ty' + 2y = sin t, y π 2 = 9, t > 0 y(t) =
For the ODE
[tex]ty'+2y=\sin t[/tex]
multiply both sides by t so that the left side can be condensed into the derivative of a product:
[tex]t^2y'+2ty=t\sin t[/tex]
[tex]\implies(t^2y)'=t\sin t[/tex]
Integrate both sides with respect to t :
[tex]t^2y=\displaystyle\int t\sin t\,\mathrm dt=\sin t-t\cos t+C[/tex]
Divide both sides by [tex]t^2[/tex] to solve for y :
[tex]y(t)=\dfrac{\sin t}{t^2}-\dfrac{\cos t}t+\dfrac C{t^2}[/tex]
Now use the initial condition to solve for C :
[tex]y\left(\dfrac\pi2\right)=9\implies9=\dfrac{\sin\frac\pi2}{\frac{\pi^2}4}-\dfrac{\cos\frac\pi2}{\frac\pi2}+\dfrac C{\frac{\pi^2}4}[/tex]
[tex]\implies9=\dfrac4{\pi^2}(1+C)[/tex]
[tex]\implies C=\dfrac{9\pi^2}4-1[/tex]
So the particular solution to the IVP is
[tex]y(t)=\dfrac{\sin t}{t^2}-\dfrac{\cos t}t+\dfrac{\frac{9\pi^2}4-1}{t^2}[/tex]
or
[tex]y(t)=\dfrac{4\sin t-4t\cos t+9\pi^2-4}{4t^2}[/tex]
what is u over 4-4= -20
u/4 - 4 = -20
Add 4 to both sides:
u/4 = -16
Multiply both sides by 4:
u = -64
Answer:
u=-64
Step-by-step explanation:
u/4 -4 = -20
First add 4 to both sides.
u/4=-16
Now multiply both sides by 4
u=-64
How do you write 416.7 in scientific notation? ___× 10^____
Answer:
4.167(10²)
Step-by-step explanation:
Step 1: Put number into proper decimal form
416.7 = 4.167
Step 2: Figure out exponent
Since we are moving the decimal places 2 places to the right, our exponent is 2
Answer:
4.167 × 10^2
Step-by-step explanation:
= 4.167 × 10^2
(scientific notation)
= 4.167e2
(scientific e notation)
= 416.7 × 10^0
(engineering notation)
(one)
= 416.7
(real number)
What number is 408% of 568?
Answer:
2317.44
Step-by-step explanation:
Solution for What is 408 percent of 568:
408 percent *568 =
(408:100)*568 =
(408*568):100 =
231744:100 = 2317.44
Answer:
2317.44
Step-by-step explanation:
2) Find the diameter.
4) If the diameter is equal to 3 inches ,d=
Answer:
d = 3 in
Step-by-step explanation:
Since we are trying to find the diameter, and the diameter is given to us as 3 in, our diameter is 3 in.