Question

for f(x)=7x and g(x)=x + 7, find the following functions. a. (f ∘ g)(x); b. (g ∘ f)(x); c. (f ∘ g)(4); d. (g ∘ f)(4)
a. (f ∘ g)(x)=
(simplify your answer.)

Explanation:

Step1: Recall composition formula

$(f\circ g)(x)=f(g(x))$.

Step2: Substitute $g(x)$ into $f(x)$

Since $f(x) = 7x$ and $g(x)=x + 7$, then $f(g(x))=7(g(x))$. Replace $g(x)$ with $x + 7$, we get $7(x + 7)$.

Step3: Simplify the expression

$7(x + 7)=7x+49$.

Answer:

$7x + 49$