5 Find all critical numbers of the function f (x) = 3Va + If there are multiple critical numbers, separate them with commas. If there are no critical numbers, input DNE. Critical Number(s): For the function f(x) - sin a + sin x on the domain [0, 27], use calculus to find the interval(s) where the function is increasing and the interval(s) where the function is decreasing. f (a) is increasing on: f(a) is decreasing on