化简x^3+y^3/x^3-y^3*x-y/x+y
问题描述：
化简x^3+y^3/x^3-y^3*x-y/x+y
答
立方和立方差公式：x^3+y^3=(x+y)(x^2-xy+y^2),x^3-y^3=(x-y)(x^2+xy+y^2)[(x^3+y^3)/(x^3-y^3)]×[(x-y)/(x+y)]=[(x+y)(x^2-xy+y^2)]/[(x-y)(x^2+xy+y^2)]×[(x-y)/(x+y)]=(x^2-xy+y^2)/(x^2+xy+y^2)这个题只有化到...