Question

How do you use integration by parts to find `intln(x) dx`?

Answer 1

By Integration by Parts: `int udv=uv-int vdu`,

Let `u=lnx` and `dv=dx`.
`Rightarrow du=dx/x` and `v=x`

`int lnx dx=xlnx-int dx=xlnx-x+C`,

where C is a constant.