Sitting here studying for a final exam this week, and I am SOO bad at identities. Maybe I just don't know them well enough.

Anyhow,

Find the solutions to the following:

I got this far...or maybe it's all wrong, I duno.

* from a Pythagorean identity

* from the reciprocal of sec?

*cross multiplied and double angle formula? I feel this wasn't a good move, haha.

Thanks in advanced!