prove the following formulas.......?

1) If f(x)= (x+1)sqrt(x^2-2x+2) then f'(x)=(2x^2-2x+1)/sqrt(x^2-2x+2)

2) If f(x)= sin(2x)/ [1+cos(2x)] then f'(x)= 2/[1+cos(2x)]

3) If f(x)= cos^2sqrt(x) then f'(x)= -sin[2sqrt(x)]/2sqrt(x)

I have no idea to solve these problems.....

Can anyone help me, please..??