Question

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Answer 1

Find the derivative of the given function.
f(x) = tan^-1 (cos x)

Using the chain rule d/dx (tan^-1 cos x) = du/dx over 1 + u^2, where u = cos(x) and d tan^-1 (u)/du = 1/u^2 + 1 = d/dx (cos x)/cos^2(x) + 1 = - sinx/ cos^2(x) + 1