(1)x+2/x-1*x^2-2x+1/x^2-x-6 - 2x-6/x^2-9

来源：百度知道 编辑：UC知道 时间：2024/05/30 19:30:05
(2)a^2-ab/a^2除(a/b-b/a)

(1)[(x+2)/(x-1)]*[(x^2-2x+1)/(x^2-x-6)-(2x-6)/(x^2-9)
=[(x+2)/(x-1)]*[(x-1)^2/(x-3)(x+2)-2(x-3)/(x+3)(x-3)
=(x-1)/(x-3)-2/(x+3)
=(x^2+2x-3-2x+6)/(x-3)(x+3)
=(x^2+3)/(x+3)(x-3)

(2)a^2-ab/a^2除(a/b-b/a)
=[a(a-b)/a^2]/[(a+b)(a-b)/ab]
=ab(a-b)/a(a+b)(a-b)
=b/(a+b)

x+2/x-1*x^2-2x+1/x^2-x-6 - 2x-6/x^2-9
=(x+2)/(x-1)*(x-1)^2/(x-3)(x+2)-2(x-3)/(x+3)(x-3)
=(x-1)/(x-3)-2/(x+3)
=[(x-1)(x+3)-2(x-3)]/(x+3)(x-3)
=(x^2+6)/(x^2-9)