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MathsMediumNumerical2022 · 24 Jun Shift 2

Q86.Let the hyperbola H : x2 −y2 = 1 and the ellipse E : 3x2 + 4y2 = 12 be such that the length of latus rectum a2 of H is equal to the length of latus rectum of E . If eH and eE are the eccentricities of H and E respectively, then the value of 12(e2H + e2E) is equal to _____.

What This Question Tests

This question tests the ability to extract parameters (a, b) from the equations of a hyperbola and an ellipse, then calculate their respective latus rectum lengths and eccentricities to satisfy the given conditions.

Concepts Tested

Standard equations of hyperbola and ellipseLength of latus rectum for hyperbola and ellipseEccentricity for hyperbola and ellipse

Formulas Used

Latus Rectum of Hyperbola = 2b^2/a

Latus Rectum of Ellipse = 2b^2/a

eH^2 = 1 + b^2/a^2

eE^2 = 1 - b^2/a^2

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