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MathsMediumMCQ2020 · 09 Jan Shift 1

Q57.If e1 and e2 are the eccentricities of the ellipse x218 + y24 = 1 9 −y24 = 1 (e1, e2) is a point on the ellipse 15x2 + 3y2 = k , then the value of k is equal to (1) 16 (2) 17 (3) 15 (4) 14

What This Question Tests

This question requires calculating the eccentricities of an ellipse and a hyperbola from their standard equations and then substituting these values into a third ellipse equation to find a constant.

Concepts Tested

Eccentricity formula for ellipse (e² = 1 - b²/a²)Eccentricity formula for hyperbola (e² = 1 + b²/a²)Condition for a point to lie on an ellipse

Formulas Used

e_ellipse² = 1 - b²/a²

e_hyperbola² = 1 + b²/a²

Equation of ellipse: 15x² + 3y² = k

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