Question

Solution

Correct option is

2x + 3y = 13

Let P(2, 3) be the given point, M be the middle point of a chord of the circle x2 + y2 = a2 through P. Then the distance of the centre O of the circle from the chord is OM.

and                  (OM)2 = (OP)2 – (PM)2                    (Fig.)

which is maximum when PM is minimum, i.e. M coincides with P i.e. Pis the middle point of the chord.

Hence the equation of the chord is

2.x + 3.y – a2 = (2)2 + (3)2 – a2    ⇒   2x + 3y = 13. 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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Q7

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Q9

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Q10

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