What is the antiderivative of xe^x?

1 Answer
Jul 8, 2016

Let u=x and dv= e^(x) dx, so du=dx and v=e^(x)

Knowing that

int u dv = uv - int v du

You can see that

int x e^(x) dx
= xe^(x)-int e^x dx
= xe^(x)-e^(x)+C

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

Explanation:

In this case, you'd have to perform integration by parts, which is given by the following formula:

int u dv = uv - int v du

Note that if you would have chosen u=e^(x) and dv = x dx, your integral would be even more complicated.