1) 3x^2-2x-8=
2)x^2+5x-14=
3)5a^2+13ac+8c^2=
因式分解..
2007-12-22 5:33 am
回答 (3)
2007-12-22 5:44 am
✔ 最佳答案
三題都可以用cross method黎計:1)3x^2-2x-8
= (3x+4)(x-2)
2)x^2+5x-14
= (x-2)(x+7)
3)5a^2+13ac+8c^2
= (5a+8c)(a+c)
參考: 自己
2007-12-22 8:08 am
1) 3x^2-2x-8=
3x\/ 4
1x/\ -2
4x-6x=-2x
(3x+4)(x-2)=3x^2-2x-8
2)x^2+5x-14=
x\/7
x/\-2
7x-2x=+5x
(x+7)(x-2)=x^2+5x-14
3)5a^2+13ac+8c^2=
5a\/+8c
a /\+1c
8ac+5ac=13ac
(5a+8c)(a+c)=5a^2+13ac+8c^2
3x\/ 4
1x/\ -2
4x-6x=-2x
(3x+4)(x-2)=3x^2-2x-8
2)x^2+5x-14=
x\/7
x/\-2
7x-2x=+5x
(x+7)(x-2)=x^2+5x-14
3)5a^2+13ac+8c^2=
5a\/+8c
a /\+1c
8ac+5ac=13ac
(5a+8c)(a+c)=5a^2+13ac+8c^2
2007-12-22 5:46 am
1) 3x^2-2x-8
=(3x+4)(x-2)
2)x^2+5x-14
=(x+7)(x-2)
3)5a^2+13ac+8c^2
=(5a+8c)(a+c)
=(3x+4)(x-2)
2)x^2+5x-14
=(x+7)(x-2)
3)5a^2+13ac+8c^2
=(5a+8c)(a+c)
參考: me
收錄日期: 2021-04-29 19:58:34
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https://hk.answers.yahoo.com/question/index?qid=20071221000051KK03404