How to integrate ln(x)?

You need to use a clever trick for this! Write ln(x) as 1ln(x), and use integration by parts:u=ln(x) v'=1u'=1/x v=xThen applying the formula we obtain∫ln(x)dx = xln(x) - ∫[(1/x)x] dx = = xln(x) - ∫1 dx = = xln(x) - x + C = x(ln(x) - 1) + CAnd if we have some data we can work out the constant of integration C.