(x/x+y +2y/x+y)乘以xy/ x+2y除以(1/x+1/y)（2）（3x^2/4y)^2乘以2y/3x+ x^2/2y^2除以2y^2/x

(x/y)^2乘以(xy)^-2除以(x^-1y) XY（XY-X2)乘以------------X-Y （xy-x^2)乘以(xy)/(x-y)= x(y-x)乘以（xy）/(x-y)= -x(x-y)乘以（xy）/(x-y)= -x^2y这样做对吗? (xy^2-2xy+x)乘以y^3-y分之y^3+y^2 x^2y-x^3/x^2+2xy+y^2÷x/x-y乘以x+y/x^2-2xy+y^2 (x/x+y +2y/x+y)乘以xy/ x+2y除以(1/x+1/y)（2）（3x^2/4y)^2乘以2y/3x+ x^2/2y^2除以2y^2/x (X-3Y)乘以(-3XY)= （xy-x²）除以xy分之x²-2xy+y²乘以x²分之x-y 计算(xy-x²) 乘以 xy/x-y (xy-x平方)乘以x-y份之xy=? 已知x=y=11,求(xy-1)的平方+（x+y-2)乘以(x+y-2xy) 1/5x的平方y乘以(-5xy)平方-(-2x)立方乘以xy立方 xy分之x^2-y^2乘以x-y分之x等于 (-x-y)(x^2+xy+y^2) 化简x^-y^/x^-2xy+y^ 2*(x-y)²(y-x)(xy) 化简：（根号x+根号y）分之(x+y） +【根号xy乘以（根号x+根号y）】 分之2xy还有一题：根号（xy） -根号（x/y）+根号（y/x)+根号（x/y+y/x+2) X-Y/2X+2Y XY/X+Y²