1. Express h(x)=cos(9x^2) as a composition of two functions f and g so that h(x)= f(g(x)).

which I ended up getting

g(x)= 9x^2 and f(x)=cosx

2. Find the domain of the function f(x)= square root of (3x+1)/(5-x)

not positive what to do here, I know that the x cant be 5 since that would make the fraction undefined.