Grade 11Analytical Geometry
Find the equation of directrix of parabola x=-2at, y=-at2
Find the equation of directrix of parabola x=-2at, y=-at2
1 Answer
Saranya Roy
The equation of directrix is y=a.As the given parametric EQ. satisfies the eq. X^2=-4aY.Thus vertex lies at (0,0) and focus and directrix are equidistant from the vertex.As it is a downward parabola so directrix is y=a
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