Consider the function f(x) = x4 − 72 x2 + 5, −5 ≤ x ≤ 13. This function has an absolute minimum value equal to __

and an absolute maximum value equal to ____

what i did is this:

f'(x) = 4(x^3)-144x

0=4(x^3)- 144x

0= 4x [ x^2 - 36 ]

36=x^2

x = 6

is this right so far?

now to check the endpoints ....

i have

-5

6

and

13

that's all i have to check right?