Find the derivative of cos-1((x - x-1)/(x + x-1)) with respect to x.

Let f(x) = tan-1(x1/3 + a1/31 - x1/3a1/3), then f'(x) equals:

Which statement about the derivative of a constant function is correct?

Which of the following correctly represents the second derivative y2 if x2 + y2 = r2?