Answer:
R-{13}
Step-by-step explanation:
We are given that
We have to find the domain of fog(x).
Domain of f(x)=R
Because it is linear function.
Domain of g(x)=R-{13}
Because the g(x) is not defined at x=13
fog(x) is not defined at x=13
Therefore, domain of fog(x)=R-{13}