找幫忙, help pls.
Let f(x) be a polynomial. If f(x) is divisible by x-1, which of following must be a factor of f(2x+1) ?
A. x
B. x-3
C. 2x-1
D. 2x+1
Explain too pls.
S4 polynomial
2012-03-19 1:16 pm
回答 (2)
2012-03-19 4:05 pm
✔ 最佳答案
Let f(x) = (x - 1)Q(x)Put x = 2y + 1, we get
f(2y + 1) = (2y + 1 - 1) Q(2y + 1)
= 2y Q(2y + 1)
which is the same as
f(2x + 1) = 2x Q(2x + 1) since y is a dummy variable.
so x is a factor of f(2x + 1). Ans. is A.
2012-03-20 10:55 am
假如可選答案改為
A. 3
B. x-3
C. 2x-1
D. 2x
答案就會是 D. 2x
一樣意思對麻?
A. 3
B. x-3
C. 2x-1
D. 2x
答案就會是 D. 2x
一樣意思對麻?
收錄日期: 2021-04-16 15:20:53
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20120319000051KK00094