Question

12) Sejam f e g funções reais definidas por
f (x) = 3x+1 e g (x) =x-2. Determine
a) f (g (5))
b) g (f (-2))
c ) f (g (x))
d) g (f (x))​

Answer 1

$f[g(x)]=3g(x)+1 \\f[g(x)]=3(x-2)+1=3x-6+1$

$f[g(x)]=3x-5$

$g[f(x)]=f(x)-2=3x+1-2=3x-1$

a)

$f[g(5)]=3.5-5=15-5=10$

b)

$=g[f(-2)]=3.(-2)-1=-6-1=-7$

c)

$f[g(x)]=3x-5$

d)

$g[f(x)]=3x-1$