Determine whether this function has a mzximum or minimum value and then find that value:

f(x)=2x^2 + 3x -9

The derivative, f'(x) = 4x +3, is zero when x = -3/4 . That means there is a relative extreme value (either maximum or minimum) there.
The second derivative is f''(x)= 4 everywhere. That means its extreme value at x = -3/4 is a minimum.