三次函數f(x) = x + bx² + cx+d通過點A(0,1) 且廣域特徵圖形近似y=2x=
5x²3
A-2. 2 (²
2x³ + bx² + c
-8+ C=1
X )= 2 (X-2) ² +A(X-²) + |
部特徵圖形近似y=4x−3,求序組(a,b,c,d)=(7,<b.16.-11)
12,-2.8
AX-2A +1= 4 x ³2/² = 2(X-2)² + B^² x -23)+ 4·¹2
fix
3
2(x - 2)² + 4(x-2) + 5
= 2X²³-6x² +12X-8 +4x-s+² = 2x² - 6x² +1bx-11
13. 若三次函數f(x)對稱中心(1,4)且圖形切 x軸於(2,0),則試求f(x)=4
X-21°+6(x-2)*+H(x-2)+8
CX-20 + 1 = 4√3²2²2²2₂B+C = 4X-3
C = 4
B=4 C = 5
A