What is the derivative of xe^(-kx)?

1 Answer
Jun 7, 2015

Assuming k as a constant, we can derivate this expression using product rule, which states that, be y=f(x)g(x), then y'=f'(x)g(x)+f(x)g'(x).

Naming f(x)=x and g(x)=e^(-kx), we have that the derivates of these are given by: f'(x)=1 and g'(x)=-ke^(-kx)

Thus,

(dy)/(dx)=1*e^(-kx)+x(-ke^(-kx))=color(green)(e^(-kx)(1-kx))