Question

Considere f(x)= x+7 e g(x)= x-9, determine:
a) (f ⁰ g) (x)
b) (g ⁰ f) (x)
c) (f ⁰ g) (2)
d) (g ⁰ f) (-2)

Answer 1

f(x) = x + 7
g(x) = x - 9

A)
f(g(x)) = x- 9 +7
f(g(x)) = x - 2

b)
g(f(x)) = x + 7 - 9
g(f(x)) = x - 2

C)
g(2) = 2 - 9
g(2) = -7

f(g(2)) = g(2) + 7
f(g(2)) = -7 + 7
f(g(2)) = 0

d)
f(-2) = - 2 + 7
f(-2) = 5

g(f(-2)) = f(-2) + 7
g(f(-2)) = 5 + 7
g(f(-2)) = 12

Espero ter ajudado.