因式分解 (x+1)(x+3)(x+5)(x+7)+15= 麻煩幫忙一下 遇到困難了?
回答 (1)
2017-05-15 11:54 am
Sol
1+7=3+5
(x+1)(x+3)(x+5)(x+)+15
=(x+1)(x+7)(x+3)(x+5)+15
=(x^2+8x+7)(x^2+8x_15)+15
p=x^2+8x
(x+1)(x+3)(x+5)(x+)+15
=(p+7)(p+15)+15
=p^2+22p+120
=(p+10)(p+12)
=(x^2+8x+10)(x^2+8x+12)
=(x^2+8x+10)(x+2)(x+6)
1+7=3+5
(x+1)(x+3)(x+5)(x+)+15
=(x+1)(x+7)(x+3)(x+5)+15
=(x^2+8x+7)(x^2+8x_15)+15
p=x^2+8x
(x+1)(x+3)(x+5)(x+)+15
=(p+7)(p+15)+15
=p^2+22p+120
=(p+10)(p+12)
=(x^2+8x+10)(x^2+8x+12)
=(x^2+8x+10)(x+2)(x+6)
收錄日期: 2021-04-30 22:14:22
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20170515034228AAhouag