Practice free →
HomeJEE MainMathematicsConic Sections › Relation between eccentricities of conjugate hyp…

Relation between eccentricities of conjugate hyperbolas:

Ae + e' = 2
Be × e' = 1
C1/e² + 1/e'² = 1
De = e'
Answer & Solution
Correct answer: C. 1/e² + 1/e'² = 1
For hyperbola x²/a² - y²/b² = 1 (e) and conjugate y²/b² - x²/a² = 1 (e'): 1/e² + 1/e'² = 1. Proof: e² = 1 + b²/a², e'² = 1 + a²/b². 1/e² = a²/(a²+b²), 1/e'² = b²/(a²+b²). Sum = 1. ✓
Solve this in the app — JEE Main practice & 24k+ MCQs →
Related questions