Question

Evaluate : `int  1/[ x(3 + log x)] dx`

Answer 1

Let I = `int 1/[ x(3 + log x)] dx`

Put log x = t

∴ `1/x dx = dt`
∴ I = `int 1/[(3 + t)] dt`
      = log `| (3 + t) |` + c
      = log `| (3 + log x) |` + c