To integrate ln x by parts, let u= ln x, dv= dx. Then du= (1/x)dx and v= x so
[tex]\int ln x= x(ln x)- \int dx= xln x- x+ C[/tex]
To integrate [itex](ln x)^2[/itex] by parts, let u= ln x, dv= ln x dx. Then du= (1/x)dx and v= xln x- x so
[tex]x(ln x)^2- x ln x- \int ln x- 1 dx= x(ln x)^2- x ln x- (x ln x - x- x)= x(ln x)^2- 2x+ C[/tex]
Keep integrating by parts until you see a pattern.