Review Key

Thanks Amy, for reminding me! =)

Here's the key. Corrections on...

#1 sec^2(x) - tan^2(x)=1, obviously
#15 add 5pi/6 + n*pi
#17 should be pi/6, 7pi/6
#34-36 replace all sqrt(65) with sqrt(85), simplify accordingly
#40&41 denominator inside the square root should be 26
#43 should be 7pi/6, 11pi/6...

This is a horrible key - too many silly errors. Time to make a new one!