Question

whats the integral of (lnt)^2

Answer 1

Integration by parts
\(u=\ln t\) then \(du=2\ln t /t\)
\(dv=dt\) then \(v=t\)
It follows that the integral is equal to
\(t\ln t-\int 2\ln t\,du\)
Then use integration by parts one more :D