Axis of a parabola is and vertex and focus are at a distance and respectively from the origin. Then, equation of the parabola is
Since, distance of vertex from origin is and focus is .
where, length of latusrectum
∴ By definition of parabola
where, PN is length of perpendicular upon , i.e. , tangent at vertex
Study 40% syllabus and score up to 100% marks in JEE