3.1 Graph of Quadratic Functions

1. The graph of quadratic function is parabola.
   
2. When the coefficient of x² is positive the graph is a parabola with ∪ shape.
3. When the coefficient of x² is negative the graph is a parabola with ∩ shape.

(A) Axis of Symmetry

The axis of symmetry is a vertical line passing through the maximum or minimum point of the parabola.