The absolute maximum value of
over the interval [-1, 1] is 1, and it occurs at x = -1/2.
The critical point you found is x = -1/2. To find the absolute maximum or minimum on the interval [-1, 1], we also need to evaluate the function at the endpoints of the interval.
Let's find p(-1):

Now, let's find p(1):

So, we have values at the critical point x = -1/2, x = -1, and x = 1:

Comparing these values, we can see that the maximum value occurs at x= -1/2, where
.
Therefore, the absolute maximum value of
over the interval [-1, 1] is 1, and it occurs at x = -1/2.