已知x²+4y²-4x+4y+5=0,求(2x-y)(x+y)/x四次方-y四次方×xy-y²/2x-y÷(y/x²+y²)²

已知x²+4y²-4x+4y+5=0,求(2x-y)(x+y)/x四次方-y四次方×xy-y²/2x-y÷(y/x²+y²)²
已知x²+4y²-4x+4y+5=0
,求(2x-y)(x+y)/x四次方-y四次方×xy-y²/2x-y÷(y/x²+y²)²

已知x²+4y²-4x+4y+5=0,求(2x-y)(x+y)/x四次方-y四次方×xy-y²/2x-y÷(y/x²+y²)²
x²+4y²-4x+4y+5=0
x²-4x+4+4y²+4y+5-4=0
(x-2)²+(2y+1)²=0
(x-2)²>=0,(2y+1)²>=0;
若使等式成立,(x-2)²=0,x=2;(2y+1)²=0,y=-1/2;
代入即可.