AP EAMCET201825 Apr 2018Morning ShiftMathematicsHyperbolaActual
If the eccentricity of a hyperbola is 5 3 , then the eccentricity of its conjugate hyperbola is
Options
- A5 3
- B5 4
- C5 2
- D8 5
Correct answer
B. 5 4
Step-by-step solution
Let the eccentricity of hyperbola and conjugate hyperbola be e 1   &   e 2 respectively. Then, 1 e 1 2 + 1 e 2 2 = 1 ⇒ 1 5 3 2 + 1 e 2 2 = 1 ⇒ 9 25 + 1 e 2 2 = 1 ⇒ 1 e 2 2 = 1 - 9 25 ⇒ 1 e 2 2 = 16 25 ⇒ e 2 = ± 5 4 But, eccentricity of hyperbola is never less than one. Hence, e 2 = 5 4 .