# Ellipse

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Definition
 Ellipse The locus of a point which moves in such a way that its distance from a fixed point bears a constant ratio $e\,$ with its distance from a fixed straight line. The fixed point is called the focus and the fixed line is called the directrix of the ellipse and $e\,$, which is less than $1$, is called the eccentricity of the ellipse. The conic section that is the intersection of a cone with a plane that does not intersect the base of the cone.

## Examples

$x^2 = 4 y\,$

$y^2 = 16 x\,$

$(x-1)^2 = 8(y+2)\,$

# Web Resources

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