back to math home page

Quadratic Function : Parabola

Quadratic Function:
Parabola : y = a ( x - h)2, where a = 1/(2p)
Vertex: V (h, 0)
foci ( h, p/2)
Graphic: Open Upward if p > 0 and Open Downward if p < 0.
Parabola equation  y = (1/4) x^2
y = (1/4) x2
Vertex: (0, 0)
Axis of symmetry: x = 0
Graphic: Open Upward
Parabola equation y = - (1/4) x^2
y = - (1/4) x2
Vertex (0, 0)
Axis of symmetry: x = 0
Graphic: Open Downward
Parabola equation y = 0.125 ( x - 3 )^2
y = 0.125 ( x - 3 )2
Vertex ( 3, 0)
Graphic: Open Upward
Parabola equation y = - 0.5 ( x + 2 )^2
y = - 0.5 ( x + 2 )2
Vertex (-2, 0)
Graphic: Open Downward
Parabola equation: x = - 1/(2p) y2
Vertex: (0, 0)
Foci: F( p/2, 0)
Directrix: x = - (p/2)
Axis of symmetry: y = 0
Graphic: Open Right
Parabola equation: x = - 1/(2p) y2
Vertex (0, 0)
Foci: F( - p/2, 0)
Directrix: x = p/2
Axis of symmetry: y = 0
Graphic: Open Left