Question

Help please! question is below!

Answer 1

Here is the question

Answer 2

Find the exact value of what?

Answer 3

cos (a+B) sorry about that

Answer 4

\[\cos (\alpha +\beta )= \cos \alpha \cos \beta -\sin \alpha \sin \beta \]

Answer 5

How do I find cos a and sin B since they are not given?

Answer 6

use the Pythagorean theorem and find the missing side. Then you can find the cosine of alpha

Answer 7

The missing side is 15. so cos of alpha would be 15/17 right? and what about sin B?

Answer 8

Draw the triangle. You know the cosine. Find the missing side and then you can find the sine.

Answer 9

So sin B is = 8/17?