интеграл 1/x в квадрате - 3x dx

int (1/(x^2-3x)dx=int (1/(3(3-x))-1/(3x))dx = int (1/(3(3-x))dx -int(1/(3x)dx =

= (1/3)*ln(x-3)-(1/3)*ln(x) +C = (1/3)*(ln(x-3)-ln(x))+C