This will use the process of integration by parts.
First, notice that ln(x)=ln(x)*1.
So, the integral of ln(x) is the integral of ln(x)1. The process of integration by parts is; int(vdu/dx)dx=vu - int(dv/dx*u)dx.
Set ln(x)=v, 1=du/dx, so int(ln(x)*1)dx = ln(x)x - int(1/xx)dx = xln(x)-int(1)dx = xln(x)-x+constant.
And you're done!