Find the derivative of f(x)=sec−1(x)f(x) = \sec^{-1}(x)f(x)=sec−1(x).
1xx2−1\frac{1}{x\sqrt{x^2-1}}xx2−11
11−x2\frac{1}{\sqrt{1-x^2}}1−x21
−1xx2−1\frac{-1}{x\sqrt{x^2-1}}xx2−1−1
11+x2\frac{1}{1+x^2}1+x21