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प्रश्न
Find the equation of a parabola with vertex at the origin and the directrix, y = 2.
उत्तर
Let the equation of the directrix be y = a.
a = 2
Equation of the parabola with directrix y =a is \[x^2 = - 4ay\]
Hence, the required equation of the parabola is \[x^2 = - 8y\]
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