NDA2025MathematicsHyperbolaActual
What is the distance between the foci of the hyperbola x^2 - 4y^2 = 1 ?
Options
- A3
- B5
- C2 3
- D2 5
Correct answer
B. 5
Step-by-step solution
The given equation of the hyperbola is x^2 - 4y^2 = 1 . This can be rewritten in the standard form as x^2 1 - y^2 1/4 = 1 . Comparing with x^2 a^2 - y^2 b^2 = 1 , we get a^2 = 1 and b^2 = 1 4 . The eccentricity e of the hyperbola is given by e = 1 + b^2 a^2 . e = 1 + 1/4 1 = 5 4 = 5 2 The distance between the foci of the hyperbola is 2ae . 2ae = 2 1 5 2 = 5 Answer: 5