[x^2-y^2(x-4y)(x+4y)-x^2-y^2(x-2y)^2]/[-(2xy)^2]

已知x*x-4xy+4y*y=0 求[2x(x+y)-y(x+y)]/(4x*x-4xy+y*y)的值? 因式分解：x×x-xy-2y×y-x-y x^2y+4xy+4y (x^-4y^)/(x^+2xy+y^)/(x+2y)/(2x^+2xy) 已知x/y=2,求2x(x+y)-y(x+y)/4x²-4xy+y² 计算(x^8-x^7y+x^5y^3-x^4y^4+x^3y^5-x^y^7+y^8)(x^2+xy+y^2) x^8-x^7y+x^6y^2-x^5y^3+x^4y^4-x^3y^5+x^2y^-xy^7+y^8 （x^2+xy/x-y)/（xy/x-y)计算 x^2-y^2/x+y-4x(x-y)+y^2/2x-y, 若(x*x+y*y)(x*x+y*y)-4x*x*y*y=0,求代数式(x*x+5xy+y*y)/(x*x+2xy+y* 作乘法:(x+y)(x^2-xy+y^2)；(x-y)(x^2+xy+y^2) [x(x^2y^2-xy)-y(x^2-x^3y)]/3x^2y