using (f ○ g)(x) = f(g(x))
substitute x =
into f(x)
f(
) = 4 / (
- 3 ) ×

=

The denominator of f(g(x)) cannot be zero as this would make f(g(x)) undefined. Equating the denominator to zero and solving gives the value that x cannot be
solve 7 - 3x = 0 ⇒ x =

domain : x ∈ ( - ∞,
) ∪ (
, + ∞ )