Hello, aargh27!

1) Simplify: .

What you did was almost correct . . .

Note that is equivalent to

. . so we have: .

. . . . . . . . . .

2) If and degrees,

find the exact values of and

First, note that is in Quadrant 3.

Since , we have: .

. . Then: .

Using double-angle identities, we have:

. .

. .

3) Find the solutions of: . in the interval

Replace with

. .

Factor: .

And we have two equations to solve:

. .

. .