1. What is [tex](g \circ f)(x)[/tex] if [tex]f(x) = \sqrt{x} - 3[/tex] and [tex]g(x) = x - 7[/tex]?

A. [tex](g \circ f)(x) = \sqrt{x-7} - 3[/tex]

B. [tex](g \circ f)(x) = \sqrt{x-10}[/tex]

C. [tex](g \circ f)(x) = \sqrt{x-3} - 7[/tex]

D. [tex](g \circ f)(x) = \sqrt{x} - 10[/tex]



Answer :

To determine [tex]\((g \circ f)(x)\)[/tex] when [tex]\(f(x) = \sqrt{x} - 3\)[/tex] and [tex]\(g(x) = x - 7\)[/tex], we need to find the composition of the functions, which is essentially [tex]\(g(f(x))\)[/tex].

Let's go through this step-by-step:

1. Evaluate [tex]\(f(x)\)[/tex]:
[tex]\(f(x) = \sqrt{x} - 3\)[/tex]

2. Substitute [tex]\(f(x)\)[/tex] into [tex]\(g(x)\)[/tex]:
First, replace [tex]\(x\)[/tex] in [tex]\(g(x)\)[/tex] with [tex]\(f(x)\)[/tex]:
[tex]\(g(f(x))\)[/tex]

3. Substitute and simplify:
Since [tex]\(f(x) = \sqrt{x} - 3\)[/tex], we substitute this into [tex]\(g\)[/tex]:
[tex]\(g(\sqrt{x} - 3)\)[/tex]
Now, replace the argument in [tex]\(g\)[/tex]:
[tex]\(g(\sqrt{x} - 3) = (\sqrt{x} - 3) - 7\)[/tex]
Simplify the expression inside [tex]\(g\)[/tex]:
[tex]\[ (\sqrt{x} - 3) - 7 = \sqrt{x} - 10 \][/tex]

Therefore, the composition [tex]\((g \circ f)(x)\)[/tex] is:
[tex]\[ (g \circ f)(x) = \sqrt{x} - 10 \][/tex]

Hence, the correct answer is:
[tex]\[ (g \circ f)(x) = \sqrt{x} - 10 \][/tex]