use f(x)=x+5 and g(x)=2 find f(f+g)(x)

1 answer

To find \( f(f+g)(x) \), we first need to determine what \( f + g \) means in this context. Typically, when we say \( f+g \), we mean the sum of the two functions applied to \( x \).

Given:

  • \( f(x) = x + 5 \)
  • \( g(x) = 2 \)

Now, let's find \( (f + g)(x) \):

\[ (f + g)(x) = f(x) + g(x) \]

Substituting the expressions for \( f(x) \) and \( g(x) \):

\[ (f + g)(x) = (x + 5) + 2 = x + 7 \]

Next, we need to find \( f(f + g)(x) \), which is:

\[ f((f + g)(x)) = f(x + 7) \]

Now, we apply the function \( f \) to \( x + 7 \):

\[ f(x + 7) = (x + 7) + 5 \]

Simplifying this gives:

\[ f(x + 7) = x + 12 \]

Therefore,

\[ f(f + g)(x) = x + 12 \]

This is the final result.