Question

Diketahui fungsi f:R -->R dengan f(x)=2x+1 dan fungsi g:R-->R dengan g(x)=x2-1. tentukanlah:
a.(fog)(x)
b.(gof)(x)
c.(gof(2)

Answer 1

F(x) = 2x + 1
g(x) = x² - 1

a) (f o g)(x) = f(x² - 1)
= 2(x² - 1) + 1
= 2x² - 1

b) (g o f)(x) = g(2x + 1)
= 2(2x + 1)² - 1
= 4x² + 8x + 1

c) (g o f)(2) = 4(2)² + 8(2) + 1
= 33