y'-2y/х=3/х^2; у=vu , y'=u'v+v'u; u'v+v'u- 2vu/x= 3/x^2 ; dv/dx=2v/x, dv/v=2dx/x, ln v= 2 ln x, v= x^2; u'x^2=3/x^2; (S-интеграл), u= S 3dx/x^4= 3 S x^-4 dx= 3* x^-3/3 + C=C-1/x^3;
у= uv= x^2 * (C- 1/x^3)
