(1/x+y)-(1/x-y)+2x/x^2-y^2

来源：学生作业帮编辑：大师作文网作业帮分类：数学作业时间：2024/11/10 13:11:18

1/(x+y)-1/(x-y)+2x/(x²-y²)
=(x-y)/[(x+y)(x-y)]-(x+y)/[(x+y)(x-y)]+2x/[(x+y)(x-y)]
=[(x-y)-(x+y)+2x]/[(x+y)(x-y)]
=(2x-2y)/[(x+y)(x-y)]
=[2(x-y)]/[(x+y)(x-y)]
=2/(x+y)

1、x(x-y)(x+y)-x(x+y)^2 (1)(x^2/x)-y-x-y [(-x-y)(-x+y)-(x+y)^2-x(y-y^2)}÷1/2y (1)(x+y)^2-(x-y)^2 1、(x-2y)(x+y) 1) (2x+5y)(2x-5y)(-4x^2-25y^2) 2) [（x+y)(x-y)-(x-y)^2+2y(x-y 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 因式分解 (1)6(x-y)^3-3y(y-x)^2 (2)x(x-y)(a-b)-y(y-x)( y=(x^2+x)/(x+1) (3x-y)^2+(3x+y)(3x-y),x=1,y=-2 （x+2)(x+3) (x-4)(x+1) (y+4)(y-2) (y-5)(y-3) 已知4x=9y求(1)x+y/y (2)y-x/2x