To find the value of \( x \) that must be excluded from the domain of the function \( \frac{f(x)}{g(x)} \), we need to identify when \( g(x) = 0 \), since dividing by zero is undefined.
Given:
- \( g(x) = x - 2 \)
Set \( g(x) \) to zero:
\[ x - 2 = 0 \]
Solving for \( x \):
\[ x = 2 \]
Thus, the value of \( x \) that must be excluded from the domain of \( \frac{f}{g}(x) \) is:
\[ \boxed{2} \]