(4x^2-y^2)/(x^2-4y^2)-(2x-y)^2/(x^2-4y^2)-(2y^2-4xy)/(4y^2-x^2)=(4x²-y²)/(x²-4y²)-(2x-y)²/(x²-4y²)-(4xy-2y²)/(x²-4y²)=(4x²-y²-4x²+4xy-y...