Вычислите: 3x^2 - xy/ 9x^2 - 6xy + y^2 при х=3/4; у= - 2/3
(3x²-xy)/(9x²-6xy+y²)=(x(3x-y))/(3x-y)²=x/(3x-y)=(3/4)/(3*(3/4)-(-2/3))=(3/4)/(35/12)=9/35