Find the derivative of the function

1.) f(x)=sqrt(cosx+sinx)

f(x)= (cosx+sinx)^1/2

f'(x)= 1/2(cosx+sinx)^-1/2 d/dx (cosx+sinx)

= ???

2.) f(x)=e^(tanx+secx)

f'(x)=e^(tanx+secx) 。d/dx(tanx+secx)

=???

3.) f(x)= ln(sin^-1 (x))

Find dy/dx by implicit differentation

1.) x sec(y)=ln(sinx)

The text in the red is what i got so far..then i got stuck..can anyone help me?