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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.

y = (1/4) x²

Vertex: (0, 0)

Axis of symmetry: x = 0

Graphic: Open Upward

y = - (1/4) x²

Vertex (0, 0)

Axis of symmetry: x = 0

Graphic: Open Downward

y = 0.125 ( x - 3 )²

Vertex ( 3, 0)

Graphic: Open Upward

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