Please help me with this

(-1, 2/3).

Step-by-step explanation:

Taking the derivative of f, we get f' = x^2 - 1 = 0.  Thus, x = -1 and x = +1.

At the relative max, y = (1/3)(-1)^3 - (-1) = -1/3 + 1 = 2/3.

The relative maximum is at (-1, 2/3).

i got 10.28 but that rounds up to 10.3

there are infinitely many solutions.