∫ 3x^2 / (1-2x^3) dx
=∫ 1 /(1-2x^3) dx^3
=1/2 ∫ 1 /(1-2x^3) d (2x^3)
=-1/2 ∫ 1 /(1-2x^3) d (1 - 2x^3)
=-1/2 ln( 1-2x^3 ) + c