handful of derivatives using trig idents, have 3 hrs

Hi. It's been some time since I've done any trig work. BTW, I'm sorry to doublepost in the calc forum, meant to post here.

Could anyone guide me through these particular problems?

I need the derivatives of the following:

1. (2 sin x)/(1+cos x)

2. (5 tan x)/(x)

3. (-8xsinxcosx)

4. (tan x - 3)/(sec x)

Also, can anyone briefly tell me what the following are equal to?

sin^2 x

cos^2 x

tan^2 x

sec^2 x

And then, how to use them in conjunction with each other.