已知x+y=2.xy=-4.求x^3y^2+x^2y^3
已知xy=-2,x-y=3,求(x+y)(x-y)-y^2+(x-y)^2-(6x^2y-2xy^2)÷2y
已知3x*+xy-2y*=0,求(x/y)-(y/x)-(x*+y*)/(xy)的值.*是平方
已知3x^2+xy-2y^2=0,求{(x+y)/(x-y)+4xy/(y^2-x^2)}/{(x+3y)*(x-y)}
已知:x-y=1,xy=-2.求:(-2xy+2x+3y)-(3xy+2y-2x)-(x+4y+xy)的值
.已知:x-y=1,xy=-2.求:(-2xy+2 x+3y)-(3xy+2y-2x)-(x+4y+xy)的值
已知x-3y=0,求(2x+y)/(x^2-2xy+y^2)X(x-y)
已知x,y>0 2x+y+3=xy 求5x+4y最小值
已知xy=-2,x-y=3,求(x+y)(x-y)-y²+(x-y)²-(6x²y-2xy
已知x+y=4.x-y=6.求代数式xy(y²+y)-y²(xy+2x)-3xy的值
已知:x/y=-2,求x^2-2xy-3y^2/x^-6xy
已知x=3y,试求(x-y)^2+2xy-y^2/x^2+7xy+y^2
已知xy/(x+y)=2求(3x-5y+3y)/(-x+3xy-y)