Diketahui:f(x+3)=2x+5 Tentukan nilai dari A.f(10); B.f(15).

f (x+3) = 2x+5
= 2(x+3) - 1
= 2x - 1
= 2x - 1
A. f(10) = 2x - 1 = 2(10)-1= 19
B.f(15) = 2x- 1= 2(15)-1= 29

Bab Fungsi
Matematika SMA Kelas X

f(x + 3) = 2x + 5
f(x + 3) = 2(x + 3) - 1
f(x) = 2x - 1

a] f(10) = 2 . 10 - 1
             = 20 - 1
             = 19

b] f(15) = 2 . 15 - 1
            = 30 - 1
            = 29