pls show steps . thx
更新1:
回 wanghei1125 你有沒有讀過數學，有沒有用過計數機:-)?
Form4 Interesting MATH
2007-02-23 7:48 am
Let f(x)=2x^3+kx^2+3x,where k is a constant.If f(-x)=-f(x),find the remainder when f(x) is divided by x+2.
pls show steps . thx
pls show steps . thx
回答 (4)
2007-02-23 8:00 am
✔ 最佳答案
Let f(x)=2x^3+kx^2+3x,where k is a constant.If f(-x)=-f(x),find the remainder when f(x) is divided by x+2.f(-x)
=-2x^3+kx^2-3x
-f(x)
=-2x^3-kx^2-3x
So k should be 0
f(x)=2x^3+3x
the remainder when f(x) is divided by x+2.
=f(-2)
=2(-2)^3+3(-2)
=-16-6
=-22
2007-02-23 8:09 am
因為f(-x)=-f(x),所以f(x)為奇函數,即k=0
則f(x)=2x^3+3x
又因為f(-2)=2*(-2)^3+3*(-2)=-22
所以餘數為-22
則f(x)=2x^3+3x
又因為f(-2)=2*(-2)^3+3*(-2)=-22
所以餘數為-22
2007-02-23 8:06 am
f(x) = 2x^3+kx^2+3x
-2x^3+kx^2-3x = -2x^3-kx^2-3x [f(-x) = -f(x)]
2kx^2=0
k=0
by long division, 2x^3+3x / x+2
remainder = 11x #
I hope I can help you.
-2x^3+kx^2-3x = -2x^3-kx^2-3x [f(-x) = -f(x)]
2kx^2=0
k=0
by long division, 2x^3+3x / x+2
remainder = 11x #
I hope I can help you.
參考: myself
收錄日期: 2021-04-25 16:52:04
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