Hi guys, im doing a Maths quiz, and have gone through the basic Trig Identity stuff, but I am stuck on 2 questions....Anyone give me an idea what to do?

Which of the following is equal to (1 − cos2y)(1 + cot2y)

A) cos(2 y) B) 1 C) sec^2y D) sin^2y

and

Which of the following is equal to

1/ (sin x X cos x) − (cos x /sin x)

A) − 1 / (sin(2 x))

B) cos^2x

C) 1

D tan x

E) 1/ sin(2 x)

F) None of the above