Find left parenthesis g circle f right parenthesis left parenthesis x right parenthesis when f left parenthesis x right parenthesis equals start root x plus 3 end root and g left parenthesis x right parenthesis equals start fraction x squared plus 2 over x end fraction.

(1 point)
Responses

left parenthesis g circle f right parenthesis left parenthesis x right parenthesis equals start fraction left parenthesis x squared plus 2 right parenthesis left parenthesis start root x plus 3 end root right parenthesis over x end fraction
Image with alt text: left parenthesis g circle f right parenthesis left parenthesis x right parenthesis equals start fraction left parenthesis x squared plus 2 right parenthesis left parenthesis start root x plus 3 end root right parenthesis over x end fraction

left parenthesis g circle f right parenthesis left parenthesis x right parenthesis equals start fraction x plus 5 over start root x plus 3 end root end fraction
Image with alt text: left parenthesis g circle f right parenthesis left parenthesis x right parenthesis equals start fraction x plus 5 over start root x plus 3 end root end fraction

left parenthesis g circle f right parenthesis left parenthesis x right parenthesis equals start fraction x squared plus 6 x plus 11 over start root x plus 3 end root end fraction
Image with alt text: left parenthesis g circle f right parenthesis left parenthesis x right parenthesis equals start fraction x squared plus 6 x plus 11 over start root x plus 3 end root end fraction

left parenthesis g circle f right parenthesis left parenthesis x right parenthesis equals start root start fraction x squared plus 2 over x end fraction plus 3 end root

1 answer

To find \( (g \circ f)(x) \), we need to evaluate the composite function, which means we first find \( f(x) \) and then substitute that into \( g(x) \).

Given:

  • \( f(x) = \sqrt{x + 3} \)
  • \( g(x) = \frac{x^2 + 2}{x} \)

Now, we calculate \( g(f(x)) \):

  1. First find \( f(x) \): \[ f(x) = \sqrt{x + 3} \]

  2. Substitute \( f(x) \) into \( g(x) \): \[ g(f(x)) = g(\sqrt{x + 3}) = \frac{(\sqrt{x + 3})^2 + 2}{\sqrt{x + 3}} \]

  3. Simplify: \[ g(f(x)) = \frac{x + 3 + 2}{\sqrt{x + 3}} = \frac{x + 5}{\sqrt{x + 3}} \]

Thus, we have: \[ (g \circ f)(x) = \frac{x + 5}{\sqrt{x + 3}} \]

Now, let's match this with the given responses. The correct answer is:

\[ (g \circ f)(x) = \frac{x + 5}{\sqrt{x + 3}} \]

This corresponds to the second response you provided:

Response: \[ (g \circ f)(x) = \frac{x + 5}{\sqrt{x + 3}} \]