Q. If $e_{1\ }$is the eccentricity of the ellipse $\frac{x^{2}}{16}$ +$\frac{y^{2}}{7}$ = 1 and $e_{2}$ is the eccentricity of the hyperbola $\frac{x^{2}}{9} - \ \ \frac{y^{2}}{7}$ $= 1$, then $e_{1} + \ e_{2}$ is equal to

A) $\frac{16}{7}$
B) $\frac{25}{4}$
C) $\frac{25}{12}$
D) $\frac{16}{9}$
Explanation

(c)
Given, ellipse $\frac{x^{2}}{16} + \frac{y^{2}}{7} = 1$
$\therefore\ \ e_{1} = \sqrt{1 - \frac{7}{16}} = \frac{3}{4}$
and hyperbola $\frac{x^{2}}{9} - \frac{y^{2}}{7} = 1$
$\therefore\ \ e_{2} = \sqrt{1 + \frac{7}{9}} = \frac{4}{3}$
Now, $e_{1} + e_{2} = \frac{3}{4} + \frac{4}{3} = \frac{25}{12}$

Dr. Abubacker
Reviewed by Dr. Abubacker

Physics Educator & NEET/JEE Specialist

Ph.D. in Physics with 19+ years of teaching experience.

Want more practice?
Practice Conic Sections MCQs