Conic Sections Question 469
Question: If e and e- are the eccentricities of the ellipse $ 5x^{2}+9y^{2}=45 $ and the hyperbola $ 5x^{2}-4y^{2}=45 $ respectively, then $ ee’= $
[EAMCET 2002]
Options:
A) 9
B) 4
C) 5
D) 1
Show Answer
Answer:
Correct Answer: D
Solution:
Clearly $ e=\frac{2}{3} $ and $ e’ $ = $ A’N=a(1+\cos \theta ) $ ,
$ \therefore $ $ ee’=1. $
BETA
