[SOLVED] Quadratic Trigonometric Equations

Hi there, I'm new. (Hi) I'd really like to get a tutor's help with this, but I can't wait until Monday, so I hope you won't mind my asking.

Anyway, this has got me really stumped. The book is no help; all the examples are much less complicated. I'll just post two examples I'm having trouble with for now.

In this section I'm supposed to find all values for :

1.)

What I tried to do was to move the 4 to the left side, convert to all sine values, and plug the values into the quadratic formula. I ended up with and . This is probably wrong, even though I'm fairly sure I didn't make any algebraic errors (I probably just chose the wrong process).

2.)

I tried converting to all sin and cos values. I think my mistake was to try to divide both sides by after that, since dividing by a variable is a no-no. I ended up with , which resulted in two correct answers (as special angles), but there are supposed to be four.

Any help is greatly appreciated and will result in my abject adoration, and cake.