Question:
If a hyperbola has length of its conjugate axis equal to 5 and the distance between its foci is 13 , then the eccentricity of the hyperbola is :
Correct Option: 1
Solution:
$\therefore$ Conjugate axis $=5$
$\therefore \quad 2 b=5$
Distance between foci $=13$
$2 a e=13$
Then, $b^{2}=a^{2}\left(e^{2}-1\right)$
$\Rightarrow a^{2}=36$
$\therefore \quad a=6$
$a e=\frac{13}{2} \Rightarrow e=\frac{13}{12}$