## Precalculus (6th Edition) Blitzer

$f$; $g(x)$
RECALL: The composition function $f \circ g$ is defined as: $(f \circ g)(x) = f(g(x))$ This means that all $x's$ in the function $f$ have to be replaced with $g(x)$ Thus, the missing expressions in the given statement (in order) are: $f$; $g(x)$