Question

Diketahui
f(x) =2x^2+1
g(x) = x+3
tentukan
(f o g) (x) ?
( g o f ) (x) ?

Answer 1

(fog)(x) = f(g(x))
=f(x+3)
=2(x+3)^2 +1
=2(x^2+6x+9) +1
=2x^2 +12x+18+1
= 2x^2 +12x+19

(gof)(x) = g ( f(x) )
=g(2x^2+1)
=(2x^2+1) +3
=2x^2 + 4