a. use composition to prove whether or not the functions are inverse of each other
b. express the domain of the compositions using interval notation.

⇒If , fog(x)=I(Identity),

  gof(x)=I(Identity),

then then f(x) and g(x) are inverses of each other.

fog(x)=x and gof(x)=x

fog=I and gof=I

It means f(x) and g(x) are inverses of each other.

⇒Domain of f(x)=R-{4}, R=Real Number

as⇒ x-4≠0

⇒x≠4

⇒Domain of g(x)=R-{0},R=Set of Real number

As, x≠0.

⇒Domain of the Composition

fog(x)=gof(x)=x

=Set of all Real Number(R)

y/x=18

step-by-step explanation:

c. (3,2,6) is the answer.