Q17 of 63 Page 202

Find the length of the line-segment joining the vertex of the parabola y2 = 4axand a point on the parabola where the line-segment makes an angle q to the x-axis.

Equation of an ellipse is y2 = 4ax, whereas


Length of latus rectum = 4a


Let the point on parabola be (i,j)


From the figure, slope of OP =



[Squaring the above mentioned equation] ------- (i)


j2 = 4ai------- (ii)









Equating the equations, {(i) & (ii)}





i = 0 (not Possible) or



Now OP =


Hence, the length of line segment is units.


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