Chapter 2: Quadratic Functions

quadratic function

a function that can be written in the form f(x) = a(x - h)2 + k, where a ≠ 0

parabola

the U-shaped graph of a quadratic function

vertex

the lowest part on a parabola that opens up or the highest point on a parabola that opens down

vertex form

f(x) = a(x - h)2 + k, where a ≠ 0 and the vertex is (h, k)

axis of symmetry

a line that divides a parabola into mirror images and passes through the vertex; the axis of symmetry is the vertical line x = h or x = -b/2a

standard form

a quadratic function written in the form f(x) = ax2 + bx + c

intercept form

a quadratic function in the form f(x) = a(x - p)(x - q)

minimum value

the y-coordinate of the vertex when a > 0

maximum value

the y-coordinate of the vertex when a < 0