Given f (x) = 8x-2x^2-5, find the maximum value of the function f (x).

Note that this is a quadratic function whose graph opens down. You could plot this function and note the coordinates of the vertex; the y-coordinate would be the max value of the function.

Alternatively, find x = - b / (2a), where a = - 2, b = 8 and c = - 5. Then find the corresponding y-value.

Alternatively, find the derivative of f (x) and set it = to 0. Solve for x. Find the y value associated with this x. That y-value is the max of f (x).