Unit circle help?

Question

Last bit of help needed, both are for the range [0, 2pi] (1 rev of the circle)

Solve (A = Angle)

cscA = -3.0

And in an equation

-2 = cos^2A - 3cosA

Answer 1

For the first one, what does that tell you about sinA or cosA?

arcsin and/or arccos is your friend.

For the second, you have a quadratic equation in cosA. Its solutions are +2 and +1. There aren't a lot of solutions to cosA = 2, but perhaps you can think of a solution to cosA = 1? :)