Question

2.a. Jika f(x) = ax+b,f(1) = 2, dan f(2)=1. Maka tentukan Bentuk fungsi f(x)
3. Diketahui f(x) = ax+b. Tentukan bentuk fungsi² berikut jika
A. F(1) = 3 dan f(2) = 5
B. F(0) = -6 dan f(3) = -5
C. F(2) = 3 dan f(4) = 4.

Answer 1

A. f(2) = 1
f(1) = 2
(2-1) a = 1- 2
a = -1 dan b = 1 - 2a --> b = 1+2 = 3
f(x) = ax+b --> f(x) = -x + 3 atau f(x) = 3 - x
.
3)
a) f(2) - f(1) = 5-3
(2-1)a = 2
a = 2 --> b = 3 - a --> b = 1
f(x) = 2x +1
.
b) f(3) - f(0) = -5 -(-6) = 1
(3-0) a = 1
a= 1/3 dan b = -5 - 3a = -5-3(1/3) = -5 -1 = -6
f(x) = 1/3x - 6
.
c)
f(4) - f(2) = 4-3 
(4-2) a = 1
2a = 1
a = 1/2  dan b = 3 - 2a --> b = 3-2(1/2) = 2
f(x) = 1/2 x + 2