x²+y²-4x+8y+20
(2x-y)²-4(x-y)(x+2y)
化简:(2x-y)²-4(x-y)(x+y)
(x+y)²+4(x+y)-5
已知x²+y²-8x+6y+25=0,求(x-y+4xy/x-y)(x+y-4xy/x+y)
4(x+y)²-20(x+y)+25
(x+y)(x-2y)(x²-4y²) 其中x=8 y=-8 化简求值
已知x²+4y²-6x+8y+13=0,求x-y/x+y的值.
因式分解 -5x³y(x-y)³+20y【x²(y-x)】²
计算:(x+y)²-4(x+y)(x-y)+4(x-y)²
化简 3(X-Y)²-4(X-Y)+7(X-Y)-6(X-Y)²
计算 [12(x+y)³(y-x)]³÷[4(x+y)²(x-y)]²
(x-2y)²+(2x-4y)(x+y)+(x+y)²