How to Integrate ln(x)?

Integrating this expression is a simple trick. We use integration by parts. For this we need a function we can integrate and a function we can differentiate. We know how to differentiate ln(x) which is 1/x. Looking at the expression we could see it as 1*ln(x) hence we can use 1 as our other funciton of x. Using the integration by parts formula given in the formula booklet we get INT(ln(x)) = xln(x) - INT(1) = x(ln(x) -1)