Найти производную f(x)=3-4x/x^2
F(x) =3-4x/x^2 f'(x) =(3-4x)^1*x^2-(3-4x) *(x^2)^1/(x^2)^2=-4x^2-2x(3-4x) /x^4=-4x^2-6x+8x^2/x^4=4x^2-6x/x^4=4x-6/x^3