Let the foci and length of the latus rectum of an ellipse be and , respectively. Then, the square of the eccentricity of the hyperbola equals ____
Answer: 51
Solution
Ellipse foci . Latus rectum .
Also (using ). Equating:
Solving the quadratic: , taking the positive root, .
Then .
The hyperbola is . Its eccentricity satisfies
Also (using ). Equating:
Solving the quadratic: , taking the positive root, .
Then .
The hyperbola is . Its eccentricity satisfies
JEE Main · 2024 · 31 Jan 2024 · Shift 1 · Integer answer