How do you find the derivative of x^tanx?

1 Answer
Aug 4, 2015

x^{tan(x)}(ln(x)*sec^{2}(x)+tan(x)/x)

Explanation:

Use logarithmic differentiation: let y=x^{tan(x)} so that ln(y)=ln(x^{tan(x)})=tan(x)ln(x).

Now differentiate both sides with respect to x, keeping in mind that y is a function of x and using the Chain Rule and Product Rule:

1/y * dy/dx=sec^{2}(x)ln(x)+tan(x)/x

Hence,

dy/dx=y * (ln(x)sec^{2}(x)+tan(x)/x)

=x^{tan(x)} (ln(x)sec^{2}(x)+tan(x)/x)