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MathsMediumMCQ2020 · 07 Jan Shift 2

Q59.If 3x + 4y = 12√2 is a tangent o the ellipse x2 + 9 = 1 for some a ∈R, then the distance between the foci a2 of the ellipse is (1) 2√7 (2) 4 (3) 2√5 (4) 2√2

What This Question Tests

This question tests the ability to find the length of a tangent from an external point to a circle, determine the equation of the chord of contact, and then calculate its length.

Concepts Tested

Equation of a circleLength of tangent from external pointEquation of chord of contactDistance between two points

Formulas Used

(x-h)^2 + (y-k)^2 = r^2

Length of tangent = sqrt(S1)

Equation of chord of contact T=0

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