Questions: If (f(x)=-2 x-5) and (g(x)=x^2+1), find (f(g(x))).
Transcript text: If $f(x)=-2 x-5$ and $g(x)=x^{\wedge} 2+1$, find $f(g(x))$.
Solution
Solution Steps
Step 1: Understand the Problem
We are given two functions, \( f(x) = -2x - 5 \) and \( g(x) = x^2 + 1 \). We need to find the composition of these functions, specifically \( f(g(x)) \).
Step 2: Substitute \( g(x) \) into \( f(x) \)
To find \( f(g(x)) \), we substitute \( g(x) = x^2 + 1 \) into \( f(x) \). This means we replace every \( x \) in \( f(x) \) with \( g(x) \).
\[
f(g(x)) = f(x^2 + 1) = -2(x^2 + 1) - 5
\]
Step 3: Simplify the Expression
Now, we simplify the expression:
\[
f(g(x)) = -2(x^2 + 1) - 5 = -2x^2 - 2 - 5
\]
Combine the constant terms:
\[
f(g(x)) = -2x^2 - 7
\]
Final Answer
The expression for \( f(g(x)) \) is \(-2x^2 - 7\). Therefore, the correct multiple-choice answer is: