Question

Sendo f(x)=(x+1)(x-1) e g(x)= 2x+1 , determine:
A)f(f(x))
B) (g o g)(2)

Answer 1

Resposta:

A)

f(x) = (x+1)(x-1) = x²-1² = x² - 1

f(f(x)) = (x²-1)² - 1

f(f(x)) = (x²-1).(x²-1) - 1

f(f(x)) = x⁴ - x² - x² + 1 - 1

f(f(x)) = x⁴ - 2x²

f(f(x)) = x² (x² - 2)

B)

g(x) = 2x+1

g(2) = 2.2 + 1

g(2) = 5

g(g(2)) = g(5)

g(5) = 2.5 + 1

gog(2) = 11