graphing parabolas

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Conic Sections Parabolas
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Vertical Horizontal
Equation
D to V or V to F is p
Vertex
Focus
Directrix
Direction of opening
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• Focus point , inside the parabola
• Vertex turning pt, or midpt of focus
• directrix
• Directrix line, outside the parabola
• P distance between vertex and focus or
• directrix

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Conic Sections
Conics Sections curves that are created by the
intersection of a plane and a right circular cone.
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Conic Sections
Conics Sections curves that are created by the
intersection of a plane and a right circular cone.
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Conics Sections
Conics Sections curves that are created by the
intersection of a plane and a right circular cone.
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Conic Sections
Conics Sections curves that are created by the
intersection of a plane and a right circular cone.
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Parabola
Focus (always inside)

• Algebraic definition
• All points that are equidistant from a given
  line called the directrix and a given fixed point
  called the focus

Both are same length
Both are same length
Directrix (always outside)
Applet
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Axis of symmetry

• The line through the focus perpendicular to the
  directrix is called the axis of symmetry of the
  parabola.

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VERTEX

• The point halfway between the focus and the
  directrix lies on the parabola.
• It is called the vertex.

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Vertical Parabola Y a(x h)2 k
Maximum (the highest point)
Minimum (the lowest point)
The axis of symmetry is vertical
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Horizontal Parabolax a(y k)2 h
The axis of symmetry is horizontal