1.(-x-y)(x-y)=( )(x+y)(y-x) 2.(2+x)(x-2)=(x+2)(x-2)两道题,
1、x(x-y)(x+y)-x(x+y)^2
[x(x-y)-y(x-y)+(x+y)(x-y)]÷2x其中x=2012 y=2013
y=(x^2+x)/(x+1)
已知X-Y/X+Y=3,求代数式2(x-y)/X+Y-3X+Y/X+Y
已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y)
(1)(x^2/x)-y-x-y
1.(x-2y)(x+2y)-(x平方+y)(x平方-y) 2.(2x-y)(y+2x)-(2y+x)(2y-x)
y'-2y=(e^x)-x
y'+2y/x=x通解
【(x-y)^2+(x+y)(x-y)】除以 2x
先化简 再求值(x-2y)(2y-x)+(2x+y)(2x-y )-(x-2y)(2x+y) 其中x=-2,y=-1.
先化简再求值(x-y)(x+y)-(x-2y) 的完全平方+x(3x-5y)-(x-y)(x-2y),其中x=1/2 y