✔ 最佳答案
螞蟻雄兵錯了:
[ (x^2+x-2)/(x^3+x^2) ] / [ (x^2+2x-3) / (x^2+3x) ]
= [ (x^2+x-2) / (x^3+x^2) ] * [ (x^2+3x) / (x^2+2x-3) ]
= (x^2+x-2)(x^2+3x) / [ (x^3+x^2)(x^2+2x-3) ]
= (x-1)(x+2) (x)(x+3) / [ (x^2)(x+1) (x-1)(x+3) ]
= (x+2) / [x(x+1)]
2010-01-26 21:32:44 補充:
[ (x^2+x-2)/(x^3+x^2) ] / [ (x^2+2x-3) / (x^2+3x) ]
= [ (x^2+x-2) / (x^3+x^2) ] * [ (x^2+3x) / (x^2+2x-3) ]
= (x^2+x-2)(x^2+3x) / [ (x^3+x^2)(x^2+2x-3) ]
= (x-1)(x+2) (x)(x+3) / [ (x^2)(x+1) (x-1)(x+3) ]
= (x+2) / [x(x+1)]
x 不等如 0,否則分母 x^3+x^2 及 x^2+3x 是 0 ,分母不可為0
ThankYou!!
2010-01-26 21:40:56 補充:
(x^3+x^2)及(x^2+3x)不可為0
x^3 + x^2 = (x^2)(x + 1) =/= 0
x =/= 0 and x =/= - 1
x^2 + 3x = x(x+3) =/= 0
x =/= 0 and x =/= - 3
x 不等如 0 , - 1 , - 3