Closed and Open Intervals? Differential Calculus

Question

If I am told to find critical numbers on the closed interval [0,2pi], are 0 and 2pi acceptable answers??? or is that only for the open interval (0,2pi)??

Answer 1

Hi Adam,

 

A closed interval includes it endpoints 

 

so yes in this case 0 and 2pi are acceptable answers

 

Hope this helps