Diketahui f(x)=2x−5 dan g(x)=x2+3x−2, nilai (g∘f)(4)=...
A. 16
B. 18
C. 23
D. 35
E. 47
Penyelesaian
Diketahui:
f(x)=2x−5
g(x)=x2+3x−2
Ditanya:(g∘f)(4)=
Jawab
(g∘f)(x)=(2x−5)2+3(2x−5)−2
(g∘f)(x)=4x2−20x+25+6x−15−2
(g∘f)(x)=4x2−14x+8
(g∘f)(4)=4(42)−14(4)+8
(g∘f)(4)=64−56+8=16
Muda Berkarya Intelektual Normatif