﻿   Find the condition that chord of contact of any external point (h, k) to the circle x2 + y2 = a2 should subtend right angle at the centre of the circle.  : Kaysons Education

# Find The Condition That Chord Of Contact Of Any External Point (h, k) To The Circle x2 + y2 = a2 should Subtend Right Angle At The Centre Of The Circle.

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## Question

### Solution

Correct option is

Equation of chord of contact of (hk)

xh + yk = a2                …(i)

Taking the equation of circle x2 + y2 – a2 = 0

Homogeneous with the help of xh + yk = a2

Sub tent 90o at the origin so

∴ Coefficient of x2 + Coefficient of y2 = 0

#### SIMILAR QUESTIONS

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Q10

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