[微積] 多項式微分
f(x) = x*(x-1)*(x-2)*(x-3) / (x-4)
求f'(0)=? 答案為3/2
可是小弟計算出來的結果為2
請問哪個答案是正確的呢?麻煩不吝嗇告知,謝謝!
小弟的計算過程:
{[x*(x-1)*(x-2)*(x-3)/(x-4)]-[0/(-4)]}/(x-0)
= x*(x-1)*(x-2)*(x-3)/x*(x-4)
= [x^(3)+3x^(2)+2x-6]/(x-4)
= [3x^(2)+6x+2]/1
f'(0)=2
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◆ From: 1.165.188.128
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不好意思,我實在找不出我哪裡出錯了?麻煩不吝嗇告知,謝謝!
※ 編輯: pigheadthree 來自: 1.165.188.128 (12/20 21:51)
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請問第三行哪裡化錯了?分子x與分母x可以消掉,這樣有錯嗎?
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※ 編輯: pigheadthree 來自: 1.165.188.128 (12/20 22:10)
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我找到原因了,我多項式的確解錯了,
應該是[x^(3)-6x^(2)+11x-6]/(x-4) = [3x^(2)-12x+11]/1 = 11????
答案為11????
※ 編輯: pigheadthree 來自: 1.165.188.128 (12/20 22:29)
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謝謝前輩們的指導,小弟大致上已了解,謝謝!
※ 編輯: pigheadthree 來自: 1.165.188.128 (12/21 06:20)
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