int ln^2 x/x^2 dx
= int ln^2 x 1/x^2 dx
= int ln^2 x d/dx(- 1/x) dx
= -1/x ln^2 x + int d/dx( (ln x)^2 ) 1/x dx
= -1/x ln^2 x + int ( 2 ln x 1/x ) 1/x dx
= -1/x ln^2 x + 2 int ln x 1/x^2 dx
= -1/x ln^2 x + 2 int ln x d/dx( -1/x) dx
= -1/x ln^2 x + 2( -1/x ln x + int d/dx( ln x ) 1/x dx)
= -1/x ln^2 x + 2( -1/x ln x + int 1/x^2 dx)
= -1/x ln^2 x + 2( -1/x ln x -1/x +C)
= -1/x ( ln^2 x + 2 ln x + 2 ) +C