Sydney simplifies the expression 2csc(-y) with the work below. What did she do wrong? 2csc(x+y)= 2/sin(x-y)
=2/cos x cos(-y)+sin xsin(-y)
=2/cos x cos y - sin xsin y
=2/cos( x +y)
= 2 sec (x + y)
Answer:
We know that:
csc(x) = 1/sin(x)
Now we want to work with:
2csc(x+y)
The first step is:
2csc(x+y)= 2/sin(x-y)
This is correct so far.
Now we need to use the relation:
sin(a + b) = sin(a)*cos(b) + sin(b)*cos(a)
Then:
sin(x - y) = sin(x)*cos(-y) + sin(-y)*cos(x)
sin(x) is an odd function, then: sin(-y) = -sin(y)
and cos(x) is an even function, then:
cos(-y) = cos(y)
Then we get:
sin(x - y) = sin(x)*cos(y) - sin(y)*cos(x)
then:
2/sin(x-y) = 2/(sin(x)*cos(y) - sin(y)*cos(x))
Now let's look at what she did:
2/sin(x-y) = 2/(cos x cos(-y)+sin xsin(-y))
Here is her error, she replaced:
sin(x - y) by cos x cos(-y)+sin(x)sin(-y)
This relation is for the cosine function, not the sine one, so here is her mistake.
Answer:
[tex]sin(\alpha -\beta )\neq cos \alpha[/tex] [tex]cos\beta +sin\alpha[/tex] [tex]sin\beta[/tex]
Step-by-step explanation:
I just did the test
the square root of 7 is between which of the following pair of number?
A.2 and 3
B.3 and 4
C.4.5 and 5.5
D.9 and 10
Answer:
A. 2 and 3
Step-by-step explanation:
The square root of 7 is 2.7 which makes it between 2 and 3.
Answer:
A
Step-by-step explanation:
because the square root of 4 is 2
and the square root of 9 is 3
since 7 is in between 4 and 9 the square root is in between 2 and 3
PLS HELP ASAP GIVING BRAINLIEST
PLZPLZPLZPLZPLZPL
1.5 im sorrry again if im wrong:(
Step-by-step explanation:
im sorry if i am wrong
Answer:
178.64 square cm
Step-by-step explanation:
5.8 x 8.8 x 2 = 102.08
8.8 x 8.7 = 76.56
76.56 + 102.08 =
178.64
Hope that helps!
Write an expression that is equivalent to
za
1
a - 4.
1
a
4 =
?
(
|
?
Answer:
½a - 4 = ? ( a - ?)
1a - 8 = -7a ( a - ?)
= ( a- 7a)
= ( -6a)
You need to know the number of different arrangements possible for five distinct letters. You decide to use the permutations rule, but your friends tells you to use 5!. Who is correct
Answer:
Both, you and your friend, are correct.
Step-by-step explanation:
5 P 5 = 5!
A shortcut I learned is that in the permutation equation nPn when n is the same on both sides, it is equal to if you used factorial, n!.
Answer:
Both Methods are correct..!!.Thanks for ASK Me...!!Find the equation of a line perpendicular to y=-3x-1 that contains the point (-1,1). Write the equation in slope intercept form.
Answer:
y = [tex]\frac{1}{3}[/tex]x + 1 [tex]\frac{1}{3}[/tex]
Step-by-step explanation:
y = -3x - 1
1. Perpendicular line needs the opposite (reciprocal) of the slope.
reciprocal of -3 is -1/3, slope 1/3. y = 1/3x + b
2. Now find the b (y-intercept). 1 = 1/3(-1) + b
1 = -1/3 + b
+ 1/3 +1/3
1 1/3 = b
3. Answer y = [tex]\frac{1}{3}[/tex]x + 1 [tex]\frac{1}{3}[/tex]
You and a friend went to Glory Days for dinner. You ordered a cheeseburger for $8.50 and a soda for $1.99. Your friend convinced you to share and split the cost of onion rings that cost $7.00. How much did you spend on your dinner?
Answer:
$13.99
Step-by-step explanation:
that's the burger and pop and half the onion rings cost combined
Express as a trinomial (x + 3)(3x + 3)
Answer:
3x^2 + 12x + 9
Step-by-step explanation:
3x • x + 3x • 3 + 3 • x + 3 • 3
For a normal distribution, what z-score value separates the lowest 25% of the scores from the rest of the distribution
Answer:
Z = -0.675.
Step-by-step explanation:
Problems of normal distributions can be solved using the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the zscore of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
What z-score value separates the lowest 25% of the scores from the rest of the distribution
This is Z which has a pvalue of 0.75, so Z = -0.675.
Can one also help me with these questions please
cAnswer: its c
Step-by-step explanation:
All the answers you need is at the top
Answer:
I don't know if you need help, but the answer to the question in the picture is indeed A. :)
What the expression is?
Answer:
29
Step-by-step explanation:
Answer:
The answer is 29
Quick answers please!!!
Answer:
Step-by-step explanation:
The higher the frequency, the higher the pitch.
so it 10000 Hz
Answer:
10,000 Hz
Explanation:
Pitch is directly proportional to frequency . Hence, 10,000 Hz has a highest pitch.
I need help understanding how to solve an equation like this I'm struggling bad
Answer:
plot 1 on the y axis first, go up one point, to the right 3, then keep this pattern going
Step-by-step explanation:
next plug in x values (1/3x)
D= domain, which is located on the x axis
for this reason, substitute D values for x
The price listed for 4 dinner plates at a home store is $23.88. What amount will Jane need to pay, if she decides to purchase 10 such dinner plates?
Amber bought 3 kg of walnuts for $6.75 per kg and 4 kg of almonds for $8.69 per kg. She gave the cashier a $100 bill. What should Amber get back in change?
Hi can someone help me out. This is due by the end of the day.
Help me please!!!!!!
Answer:
BStep-by-step explanation:
:)))))))))))))))))))Louis wants to carpet the rectangular floor of his basement. The basement has an area of 4,335 square feet. The width of the basement is
3/5 its length. What is the length of Louis's basement? The length is blank feet.
Answer:
The length of Louis's basement is 85 feet.
Step-by-step explanation:
The area of the basement, A = 4,335 square feet
The width of the basement is 3/5 its length.
Let length be l.
Width = (3/5)l
The area of the basement is given by :
[tex]A=l\times b\\\\4,335 =l\times \dfrac{3}{5}l\\\\4,335 =\dfrac{3}{5}l^2\\\\l^2=\dfrac{4,335 \times 5}{3}\\\\l=\sqrt{\dfrac{4335\times5}{3}}\\\\l=85\ ft[/tex]
So, the length of Louis's basement is 85 feet.
Need help! (5 3/4 1 5/6) - 6 7/12
Answer:
Step-by-step explanation:
7/12 / 3/10 = 35/
18
= 1 17/
18
≅ 1.9444444
Line C passes through points (0, 2) and (8,8). What is the slope of a line parallel to line C?
Answer:
below
Step-by-step explanation:
If line C is parallel to another line, they will have the same slope. so calculate the slope first:
8-2/8-0=3/4(simplified)
and thats it
Ms. Parker earns $5 per hour babysitting. She already had $2 before she started. How
many hours does she have to babysit to have $22?
Answer:
4 hours
Step-by-step explanation:
simply multiply
Figure D'E'F'G'is a dilation with center (0,0) of figure DEFG. What is the scale factor? Enter your answer in the box.
The scale factor is 4.
Important information:
Figure D'E'F'G' is a dilation with center (0,0) of figure DEFG. Scale factor:From the given figure it is clear that:
DG = 2
D'G' = 8
The scale factor is:
[tex]k=\dfrac{D'G'}{DG}[/tex]
[tex]k=\dfrac{8}{2}[/tex]
[tex]k=4[/tex]
Therefore, the scale factor is 4.
Find out more about 'Scale factor' here:
https://brainly.com/question/19896181
A baker needs 15lb of cream cheese that contains 20% fat to fill a big order. But his supplier delivers one cream cheese that contains 10% fat, and another that contains 35% fat. How many pounds of each should a baker combine to fill the order?
Pls help if you answer u will get 40 points
Answer:
136.5 g
Step-by-step explanation:
I need help please i really need it (14 points)
Answer:
point b
Step-by-step explanation
piont b can go to piont e
Answer:
B
Step-by-step explanation:
Go through each point and see which ones works:
- 2x – 117 = = 10x + 59
Answer:
[tex]\huge\boxed{x=-\dfrac{44}{3}=-14\dfrac{2}{3}}[/tex]
Step-by-step explanation:
[tex]-2x-117=10x+59\qquad|\text{add 177 to both sides and subtract}\ 10x\ \text{from both sides}\\\\-2x-10x-117+117=10x-10x+59+117\\\\-12x=176\qquad|\text{divide both sides by (-12)}\\\\\dfrac{-12x}{-12}=\dfrac{176}{-12}\\\\x=-\dfrac{176:4}{12:4}\\\\x=-\dfrac{44}{3}[/tex]
The trapezoids below are similar. Find the two missing side lengths.
Answer:
y = 15, x = 4
Step-by-step explanation:
Hope this helped!
Answer:
y+15x=4
Step-by-step explanation:
help me pliss
which one is supposed to be correct?
Given the statement ΔQRS ≅ ΔXYZ, list all congruent parts you can conclude about the two triangles. Explain.
Answer:
Side QR is congruent to Side XY.
Side RS is congruent to Side YZ.
Side SQ is congruent to Side ZX.
Angle Q is congruent to Angle X.
Angle R is congruent to Angle Y.
Angle S is congruent to Angle Z.
Step-by-step explanation:
Side QR is congruent to Side XY because triangle QRS is congruent to triangle XYZ and each point of a triangle is in corresponding order with a point of the other triangle. For example, Q matches up with X since they both are listed first in their respective sequence.
Find m\angle Am∠Am, angle, A.
Round to the nearest degree.
Answer:
m∠A = 106°
Step-by-step explanation:
All three sides of the triangle are given in the question.
To find the measure of included angle A between two sides we will apply cosine formula,
BC²= AB² + AC² - 2(AB)(AC)cosA
(13)² = (10)² + (6)² - 2(10)(6)cosA
169 = 100 + 36 - 120cosA
cosA = [tex]\frac{-169+136}{120}[/tex]
cosA = -0.275
A = [tex]\text{cos}^{-1}(-0.275)[/tex]
A = 105.96°
A ≈ 106°
Therefore, m∠A = 106° will be the answer.