Given eccentricity (e), directrix (d), and angle θ, this determines the vertical and horizontal directrix polar equations.

This calculator has 3 inputs.

This calculator has 3 inputs.

- r = ed/(1 - e cos(θ))

r = ed/(1 + e cos(θ))

r = ed/(1 - e sin(θ))

r = ed/(1 + e sin(θ))

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- angle
- the figure formed by two rays, called the sides of the angle, sharing a common endpoint, called the vertex of the angle.
- conic
- directrix
- line in a parabola not through the focus
- eccentricity
- Deviation of a conic from a circular shape
- polar conics
- polar equation
- any equation that describes a relation between r and θ