﻿ If P, Q, R are three points on a parabola y2 = 4ax whose ordinates are in geometrical progression, then the tangents at P and R meet on : Kaysons Education

# If P, Q, R are Three Points On A Parabola y2 = 4ax whose Ordinates Are In Geometrical Progression, Then The Tangents At P and R meet On

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## Question

### Solution

Correct option is

The line through Q parallel to y-axis

Let the coordinates of P, Q, R be (ati2, 2ati)i = 1, 2, 3 having ordinates in G.P. So that t1t2t3 are also in G.P. i.e. t1t3 = t22. Equations of the tangents at P and R are

ty = x + at12 and t3 y = x + at32, which intersect at the point

Which is a line through Q parallel to y-axis.

#### SIMILAR QUESTIONS

Q1

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Q2

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Q3

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Q4

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Q5

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Q6

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