A quadratic function will contain a squared term, but will have no higher power. Plotted on a graph, it will be in the shape of a parabola, which is a curve that comes to a rounded point then turns to curve back again.
The point at which it turns is a turning point, and this will be either a minimum or a maximum value. Curves can fall, turn, and rise again; or they may rise, peak, and fall.
Draw graphs as accurately to obtain any turning points or roots.
1. Plot the graph y = x2 - 3.
The graph y = x2 - 3 may be plotted using the following points:
|x2 - 3||13||6||1||-2||-3||-2||1||6||13|
2. For the graph, above: is the turning point a minimum value or a maximum value?
The point at which the graph turns is the lowest point for the line. It is therefore a minimum point.