Calculus III
posted by Sean .
Derivative of Inverse Trigonometric Functions
f(x) = cos(arcsin(2x))
What is f'(x)?

I did this down below, after the one drwls answered

copied:
It is so similar that you should be able to do it the same way. Draw the triangle and you have sqrt(14x^2)
f(x) = (14x^2)^.5
f'(x) = .5 [(14x^2)^.5] (8x)
= 4x/sqrt(14x^2) 
Oh.
But the text book I'm using gives me the answer:
Sqrt(14x^2)
No denominators or anything. 
That is just the first step.