# How do you use a double-angle formula to find the exact value of cos2u when sin u = 7/25, where pi/2 <u < pi?

##### 1 Answer

Write your answer here...

Start with a one sentence answer

Then teach the underlying concepts

Don't copy without citing sources

preview

?

#### Answer

Write a one sentence answer...

#### Answer:

#### Explanation

Explain in detail...

#### Explanation:

I want someone to double check my answer

Ratnaker Mehta
Share

Feb 17, 2017

Was this helpful? Let the contributor know!

Describe your changes (optional) 200