Question

1. Diketahui fungsi : f(x) = 3x+5. Tentukan :
a. f(3)
b. f(-4)
c. f(-8)

2. A = { a,b,c }
B = {1,2,3,4}
Berapa pemetaan yang mungkin dari A ke B?

3. f(x) = 5x + m
f(3) = 19.
Tentukan :
a. Nilai M
b. Rumus Fungsi :
c. f(8)

4. Diketahui f(x) = ax + b. f(2) = 11, f(-4) = -7
Tentukan :
A. a= ... b=...
B. Rumus fungsi :
c. f(6)

Answer 1

1) f(x) = 3x+5
f(3)  = 3(3)+5 = 9+5= 14
f(-4) = -12+5 = -7
f(-8) = -24+5 = - 19

2. n(A) = 3, n(B) = 4
banyak pemetaan dariAke B = 4³ = 64

3) f(x) = 5x + m
f(3)  = 19
15 + m = 19 
m = 4
f(x) = 5x + 4
f(8) = 5(8)+4 = 44

4. f(x)= ax+b
f(2) = 11
f(4) = -7
(2-(-4)) a = 11-(-7)
6a = 18
a =3
b = 11 - 2a = 11 -6  
b= 5
f(x) = 3x + 5
f(6) = 3(6)+ 5 =  23