This question seems really easy, but I can't seem to work it out.

Prove that:

EDITTED: SEE BELOW

These are the identities we can use:

$\displaystyle Cos^2\theta+Sin^2\theta=1$

$\displaystyle \frac{Sin\theta}{cos\theta}=tan\theta$

$\displaystyle 1+tan^2\theta=sec^2\theta$

$\displaystyle cosec^2\theta=1+cot^2\theta$

Thanks in advance for any help, please check back after posting as I may have a few problems.

Apologies, I've worked it out by myself. I'll edit the post if I have any other issues. Sorry for wasting anyone's time.