已知:x+y=5,x^2+y^2=11,求代数式x^3y-2x^2y^2+xy^3的值

已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) 已知|x-2y+11+1x+y-5|=0项X-Y的值 已知x*x+4x+y*y-2y+5=0,则x*x+y*y=? 已知x+y/y=11/8,求x-y/x+2y的值. 已知x+y/x=11/8,求x-y/x+2y的值 (3x-2y)(4x-5y)-11(x+y)(x-y)+5xy,已知X=3又1/2,y=2又1/3 已知x=2,y=3,求代数式（x-y）*（x-y）^3*(x-y)^5*……*(x-y)^11 已知x-y=3,求[（x+y)(x-y)-(x-y)^2+2y(x-y)]除以的值 已知3x =2y 求x/x+y+y/x-y-y²/x²-y² x-y/x-x+y/y-(x+y)(x-y)/y² y/x=2 已知f(x+y,y/x)=x^2-y^2,则f(x,y)= 已知|x|=2,|y|=3,|x+y|=-(x+y)求x-y 已知x≠y,x^2-x=y^2-y,求x+y的值. 已知x>0,Y>0,如何证x^2/y+y^2/x>=x+y 已知X.x+y.y-4x+2y+5=0,求4X.X-12X Y+9Y.y的值 已知x+y=a,2x-y=-2a,求[（x/y-y/x)/(x+y)-x(1/x-1/y)]/[(x+1)/y]的值 4(x-y)-3(x-y)=9 5(x-y)+2(x-y)=11 3(x+y)-4(x-y)=11,2(x-y)+5(x+y)=27