已知(x+y)^2-2x-2y+1=0,求2x^2+2xy+3y^2-2x-3y
已知3x^2+xy-2y^2=0,求{(x+y)/(x-y)+4xy/(y^2-x^2)}/{(x+3y)*(x-y)}
已知3x*+xy-2y*=0,求(x/y)-(y/x)-(x*+y*)/(xy)的值.*是平方
已知x-3y=0,求(2x+y)/(x^2-2xy+y^2)X(x-y)
已知x*x-4xy+4y*y=0 求[2x(x+y)-y(x+y)]/(4x*x-4xy+y*y)的值?
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)-y^2+(x-y)^2-(6x^2y-2xy^2)÷2y
已知x^2-3y^2=2xy(x>0,y>0),求代数式x+2y/x-y
已知x-3y=0,求(2x+y)/(x^2-2xy+y^2)*(x-y)的值
已知x-3y=0,求(2x+y)/(x^2-2xy+y^2)*(x-y)的值.
已知x-3y=0,求(2x+y)(x-y)/x^2-2xy+y^2的值
已知x-3y=0,求2x+y/x-2xy+y乘(x-y)的值
已知3/(x-y)=1/xy 求(-x-2xy+y)/ (2x+3xy-2y)