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2 years ago

Verify this cofunction identity by using the difference identity for cosine. Show your work! cos⁡(π/2-θ)=sinθ

1 answer:

8 0

Cos(A-B) = cosAcosB + sinAsinB

cos(π/2 - θ) = cos(π/2)cosθ + sin(π/2)sinθ

π/2 = 90°
cos(π/2) = cos90° = 0. sin(π/2) = sin90° = 1

cos(π/2 - θ) = cos(π/2)cosθ + sin(π/2)sinθ

= 0*cosθ + 1*sinθ = sinθ

Therefore cos(π/2 - θ) = sinθ

QED

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Evangeline is making snack bags for her class. If she can fill 5/8 of her snack bags with 1 2/3 cups of pretzels, how many cups

brilliants [131]

Answer:

2 2/3

Step-by-step explanation:

For each of her snack bag, she can fill it with a 1/3 cup of pretzels

1/3 x 8 = 2 2/3 cups

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2 years ago

Write a function rule for the following arithmetic sequence and use it to find the 224th term. Show your work.

zavuch27 [327]

Answer:

671 is the 224th term of the given series

Step-by-step explanation:

The given sequence is

2,5,8,11....

First term that is 2

common difference that is 3

we have to find 224th term

That is n =224

using $a_n=a+(n-1)d$

$a_{224}=2+(224-1)3$

On solving the above equation we get

$a_{224}=671$

Hence, 224th term of the given series is 671

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2 years ago

Read 2 more answers

A company buys pens at the rate of $7.50 per box for the first 10 boxes, $5.50 per box for the next 10 boxes, and $4.50 per box

photoshop1234 [79]

So it is really easy to solve firstly we can see how much does the first 10 boxes make which makes around 75$ obviously. Secondly 55$ for the next 10 boxes.

So for now we can simply calculate that we have spent around 130$ which means 20 boxes. The remaining money left is 18$ so we can buy 18/4.5 = 4 only 4 boxes with that money. Hence a total of 24 boxes.

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2 years ago

Aiko is finding the sum (4 + 5i) + (-3 + 7i). She rewrites the sum as (-3 + 7)i + (4 + 5)i. Which statement explains the

Doss [256]

Answer:

Aiko should not have put both of the 'i' out of the brackets.

Step-by-step explanation:

As only one integer has i with it, it is not possible to take the i out of the bracket.

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2 years ago

What are two pair fractions with common denominators for 3/5 and 3/4

diamong [38]

The cheap answer is, you simply "grab the denominator of one and multiply it times the other's top and bottom", so let's do so,

$\bf \cfrac{3}{5}\cdot \cfrac{4}{4}\implies \cfrac{12}{20}\qquad \qquad \qquad \qquad \qquad \cfrac{3}{4}\cdot \cfrac{5}{5}\implies \cfrac{15}{20}$

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2 years ago