What is the antiderivative of (ln x)^2/x^2?

1 Answer
Aug 29, 2016

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

Explanation:

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