Question

阿羅哈

想請問一下這題～～～～～
算好多遍 每次算出來的答案都不一樣😭😭
想問說是哪裡算錯了～～
謝謝🙏
答案是9x^3-3x^2+2

已知二次函數(r)在x=2時有極小值-2,且此圖形在 (3,2)與直線y=9x-25
相切,則(x) = _

an
又
f(3) = 2
f'(3)-9
.a
2.
f(2)=-2.
Hin)39(*-)(8 + b)
+(2)=0
239 (8 6x-28-26)
= 30 x + 3.0 (6-2) X-bab.
u f(x)= aga(b->);"- baby to
f(2)=-214 x 3-8 at 6a (6-2)-12 a b F (= -2.
"20a-bab + 6 = -2
{(1)=216172921224: (6-2) -189b+c=2
-goberC-2
f'(²)=0/tix & f'(2) = - bab= 0 - ②
+' (3)=9 / 4X > 1'(3) = 27 arba (6-2)-bab=9
in qa+3a6 = 8
ibarab=
30
in. -D: 4 200 + ab 4.
01:30gu20
@x
06:21 - sort
,
3
|
|
1
* abst—
q ga 3 ab=
at
a = 1/4; $0 20 b=0
"

Answer 1

✨ Jawaban Terbaik ✨

Ny-Ålesund

你的答案是錯的!
供參考：假設方程式為 y = ax^3 + bx^2 + cx + d
f(2) = -2
f(3) = 2
f'(2) = 0
f'(3) = 9
硬算

阿羅哈

原來如此！謝謝你