5X²-3Y²-(X²-Y²)-2(X²+4Y²)其中|X+
x(x-y)-y(y-x)+(x-y)²因式分解
5X²-3Y²-(X²-Y²)-2(X²+4Y²)其中|X+
已知x-y=1,y≠0,求{(x+2y)²+(2x+y)(x+4y)-3(x+y)(x-y)}÷y的值.
计算:(1)2/(x+y)+4y/x²-y²(2)x²/x+y-x+y
[(2x+y)²-y(y+4x)-8x] ÷2x 其中x=2,y=-1
因式分解x²(x-2y)+y²(2y-x)
先化简,在求值:〔(x+2y)(x-2y)-(x+4y)²〕÷4y,其中x=-5,y=2,
先化简,再求值:x²/x-y-y²/x-y,其中x=1+2又根号3
(2x+y)²-y(y+4x)-8x等于?
先化简再求值:(x-2y)²-(x+2y)(x-2y)-(x-3y)(x-y).其中x²+9y
x²+y²-4x+6y+13=0,求(3x+y)²-3(3x+y)(x+y)-(x-3y)
2(x³-2y²)-(x-2y)-(x-3y²+2x³)其中x=﹣3,y=﹣2