Warm up Graph the Function using a table Use x values -1,0,1,2,3 x2 - 2x + 3

9.1 Graphing Quadratic Functions

Vocab Quadratic Function – Highest power of x is 2 (x2) Standard Form – ax2 + bx + c, a ≠ 0 Parabola – the U shaped graph of a quadratic Axis of symmetry – A line down the middle of the parabola Vertex – The bottom/top of the graph

Minimum – when a is positive (a>0) the parabola opens upward, the vertex is the minimum. Maximum – when a is negative (a<0) the parabola opens down, the vertex is a maximum

Example 1 Since the graph does not go below y = -7, The range is {y|y ≥ -7} The Domain is all real numbers.

Example 2 Vertex: (-1,0) minimum Axis of symmetry: x = -1 Y-intercept: (0,1) Vertex: (2,3) maximum Axis of symmetry: x = 2 Y-intercept: (0,-1)

Example 3 Step 1: find the axis of symmetry Step 2: use the axis of symmetry to find the y value of the vertex

Example 4 Domain (x’s) is all real numbers Range is {y|y<8)

Example 5

Worksheet