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.

Plot the graph `y = x^2 - 3`.

The graph *y* = *x*^{2} - 3 may be plotted using the following points:

`x` | -4 | -3 | -2 | -1 | 0 | 1 | 2 | 3 | 4 |

`x^2 - 3` | 13 | 6 | 1 | -2 | -3 | -2 | 1 | 6 | 13 |

Answer:

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.

Answer: Minimum

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