How do you integrate y=xe^(-x)y=xex?

1 Answer
Jul 4, 2016

= -e^{-x} (x +1) + C=ex(x+1)+C

Explanation:

int dx qquad x e^{-x}

IBP: int u v' = uv - int u'v

here

u = x, u' = 1
v' = e^{-x}, v = - e^{-x}

so

-x e^{-x} - int dx qquad (-e^{-x})

= -x e^{-x} - (e^{-x}) + C

= -e^{-x} (x +1) + C