Maximum–Minimum Problems
We have seen that for any quadratic function f(x) = ax2 + bx + c, value of f(x) at the vertex is either a maximum or a minimum, meaning that either all outputs are smaller than that value for a maximum or larger than that value for a minimum.
There are many types of applied problems in which we want to find a maximum or minimum value of a quadratic function can be used as a model, we can find such maximums or minimums by finding coordinates of the vertex.