1、(x+y)-(x+y)^32、x(x-y)-y(y-x)3、(a-b)^2-4b+4a4、a^n+1+a^n+a^n-15、x(x+y)(x-y)-x(x+y)^26、已知a+c-7=0,求(a+b)^2-2a(b-c)-2b(b-c)+(c-b)^2的值7、x^2-8y^2(x^2-2y^2)

{(x,y) |x|+|y| x>y?x:y (x+y)(x-y)+4(y-1) x^/y-x-y^/y-x化简. 化简x(y-x)-y(x-y) 行列式计算 x y x+y y x+y x x+y x y|x y x+y ||y x+y x ||x+y x y | y/(x+y)-x/(x-y) [(-x-y)(-x+y)-(x+y)^2-x(y-y^2)}÷1/2y x>=1,x-y y=x-1(x 因式分解x(x+y)(x-y)-x(x+y)^2 x(x+y)(x-y)-x(x+y)的平方 x(x+y)(x-y)-x(x+y)² 因式分解 x-y/x-x+y/y-(x+y)(x-y)/y² y/x=2 (x/x+y-x/y-x-2xy/x.x-y.y)/(1/x-1/y) 分式化简 计算：(1+ y/x-y )·(1- x/x+y) 感激不尽1.x,y满足(x-y-1)(x+y) (1-y+x/y)除以y平方-x平方/x