What is the derivative of x^(cosx)?

1 Answer
Jun 3, 2016

(dy)/dx = x^{cos(x)} (cos(x)/x - sin(x) log_e x)

Explanation:

y = x^{cos(x)} equiv log_e y = cos(x) log_e x
Deriving the log transformed equation we have
dy/y = -sin(x)log_e x dx+cos(x)/x dx
grouping
(dy)/dx = y(cos(x)/x - sin(x) log_e x)
and finally
(dy)/dx = x^{cos(x)} (cos(x)/x - sin(x) log_e x)