Given [tex]f(x) = 2x[/tex] and [tex]g(x) = x^2 + 3[/tex], find [tex]g(f(x))[/tex].

A. [tex]4x^2 + 3[/tex]
B. [tex]x^2 + 2x + 3[/tex]
C. [tex]2x^2 + 3[/tex]
D. [tex]2x^2 + 6[/tex]



Answer :

To solve for [tex]\( g(f(x)) \)[/tex], we'll follow these steps:

1. Determine the function [tex]\( f(x) \)[/tex]:
[tex]\[ f(x) = 2x \][/tex]

2. Determine the function [tex]\( g(x) \)[/tex]:
[tex]\[ g(x) = x^2 + 3 \][/tex]

3. Substitute [tex]\( f(x) \)[/tex] into [tex]\( g(x) \)[/tex]:

We need to find [tex]\( g(f(x)) \)[/tex]. This means we will substitute the entire expression of [tex]\( f(x) \)[/tex] into the function [tex]\( g(x) \)[/tex].

So, let's substitute [tex]\( 2x \)[/tex] (which is [tex]\( f(x) \)[/tex]) into [tex]\( g(x) \)[/tex]:
[tex]\[ g(f(x)) = g(2x) \][/tex]

4. Evaluate [tex]\( g(2x) \)[/tex] using the definition of [tex]\( g(x) \)[/tex]:
[tex]\[ g(2x) = (2x)^2 + 3 \][/tex]

5. Simplify the expression [tex]\( (2x)^2 + 3 \)[/tex]:
[tex]\[ (2x)^2 = 4x^2 \][/tex]
Thus,
[tex]\[ (2x)^2 + 3 = 4x^2 + 3 \][/tex]

Therefore, [tex]\( g(f(x)) = 4x^2 + 3 \)[/tex].

The correct answer is
[tex]\[ 4x^2 + 3 \][/tex]