6X^2 +18X = 0
15X=5X^2
X^2-49=0
25X^2-64=0
4條因式分解!!!!!!!!!!!!!!!!!!!!!!!!
2011-09-03 4:53 pm
回答 (3)
2011-09-03 5:24 pm
✔ 最佳答案
6x^2+18x = 0x^2+3x=0
x(x+3)=0
x=0 or x+3=0
x=0or x=－3
15x=5x^2
5x^2－15x=0
x^2－3x=0
x(x－3)=0
x=0 or x－3=0
x=0 or x=3
x^2－49=0
x^2－7^2=0
(x－7)(x+7)=0
x－7=0 or x+7=0
x=7 or x=－7
25x^2－64=0
(5x)^2－8^2=0
(5x－8)(5x+8)=0
5x－8=0 or 5x+8=0
x=8/5or x=－8/5
2011-09-04 1:34 am
6X^2 +18X = 0
6(x^2+3x)=0
x^2+3x=0
x(x+3)=0
x=0 or x=-3
15X=5X^2
-5x^2+15x=0
5x^2-15x=0
5(x^2-3x)=0
x^2-3x=0
x(x-3)=0
x=0 or x=3
X^2-49=0
(x+7)(x-7)=0
x=7 or x=-7
25X^2-64=0
(5x+8)(5x-8)=0
x=-8/5 or x=8/5
6(x^2+3x)=0
x^2+3x=0
x(x+3)=0
x=0 or x=-3
15X=5X^2
-5x^2+15x=0
5x^2-15x=0
5(x^2-3x)=0
x^2-3x=0
x(x-3)=0
x=0 or x=3
X^2-49=0
(x+7)(x-7)=0
x=7 or x=-7
25X^2-64=0
(5x+8)(5x-8)=0
x=-8/5 or x=8/5
參考: a^2-b^2=(a+b)(a-b)
2011-09-03 7:07 pm
6x^2+18x=0
6x(x+3)=0
x=0 or-3
15x=5x^2
0=5x^2-15x
5x^2-15x=0
5x(x-3)=0
x=0 or 3
x^2-49=0
x^2-7^2=0
(x+7)(x-7)=0
x=-7 or 7
25x^2-64=0
(5x)^2-8^2=0
(5x+8)(5x-8)=0
x=-8/5 or 8/5
6x(x+3)=0
x=0 or-3
15x=5x^2
0=5x^2-15x
5x^2-15x=0
5x(x-3)=0
x=0 or 3
x^2-49=0
x^2-7^2=0
(x+7)(x-7)=0
x=-7 or 7
25x^2-64=0
(5x)^2-8^2=0
(5x+8)(5x-8)=0
x=-8/5 or 8/5
參考: me
收錄日期: 2021-04-13 18:12:56
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20110903000051KK00169