F.4 mathematics
回答 (2)
2012-04-11 11:15 pm
✔ 最佳答案
代 x = 3:9a + 3b - 7 = 14
9a + 3b = 21 ... (1)
代 x = -3:
18 - 3a + b = 1
3a - b = 17 ... (2)
得 a = 4, b = -5
參考: 原創答案
2012-04-11 11:19 pm
Let q be the quotient:
ax^2+bx-7=(x-3)q+14
代3入x9a+3b-7=14
9a+3b=21
3a+b=7-----(1)
----------------------------
2x^2+ax+b=(x+3)q+1
代-3入x
18-3a+b=1
3a-b=17(2)
----------------------
(1)+(2):6a=24
a=4//
3a+b=7
12+b=7
b= -5//
ax^2+bx-7=(x-3)q+14
代3入x9a+3b-7=14
9a+3b=21
3a+b=7-----(1)
----------------------------
2x^2+ax+b=(x+3)q+1
代-3入x
18-3a+b=1
3a-b=17(2)
----------------------
(1)+(2):6a=24
a=4//
3a+b=7
12+b=7
b= -5//
收錄日期: 2021-04-13 18:37:25
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20120411000051KK00539