All categories

2 years ago

30 POINTS! The question is in the image! Answer choices: 8, 4, 7, 9

Mathematics

1 answer:

Ahat [919]2 years ago

3 0

$\bold{ANSWER:}$
EF = 7ft

$\bold{EXPLANATIONS:}$

You might be interested in

Who is my favorite person ever?

blondinia [14]

The answer would obviously be :

5 0

3 years ago

Please help! Will give Brainliest!

Serhud [2]

Answer:

Step-by-step explanation:

8 0

3 years ago

Rewrite with only sin x and cos x.

Annette [7]

Option A

$\cos 3 x=\cos x-4 \cos x \sin ^{2} x$

<em><u>Solution:</u></em>

Given that we have to rewrite with only sin x and cos x

Given is cos 3x

$cos 3x = cos(x + 2x)$

We know that,

$\cos (a+b)=\cos a \cos b-\sin a \sin b$

Therefore,

$\cos (x+2 x)=\cos x \cos 2 x-\sin x \sin 2 x$ ---- eqn 1

We know that,

$\sin 2 x=2 \sin x \cos x$

$\cos 2 x=\cos ^{2} x-\sin ^{2} x$

Substituting these values in eqn 1

$\cos (x+2 x)=\cos x\left(\cos ^{2} x-\sin ^{2} x\right)-\sin x(2 \sin x \cos x)$ -------- eqn 2

We know that,

$\cos ^{2} x-\sin ^{2} x=1-2 \sin ^{2} x$

Applying this in above eqn 2, we get

$\cos (x+2 x)=\cos x\left(1-2 \sin ^{2} x\right)-\sin x(2 \sin x \cos x)$

$\begin{aligned}&\cos (x+2 x)=\cos x-2 \sin ^{2} x \cos x-2 \sin ^{2} x \cos x\\\\&\cos (x+2 x)=\cos x-4 \sin ^{2} x \cos x\end{aligned}$

$\cos (x+2 x)=\cos x-4 \cos x \sin ^{2} x$

Therefore,

$\cos 3 x=\cos x-4 \cos x \sin ^{2} x$

Option A is correct

7 0

3 years ago

We are going to sell Harlem Sweatshirts to raise money for

son4ous [18]

Answer:

32 sweatshirts

Step-by-step explanation:

profit per sweatshirt 28-13=$15

475/15=31.66667

3 0

3 years ago

I need the word for this definition..... a number is the product of that number and any whole number

Oxana [17]

The answer to that definition is a multiple. A multiple is any number that is not zero.

Hope I helped!

- Amber

4 0

3 years ago