If distance between the directrices be thrice the distance betwee… - Vidyadip

MCQ

If distance between the directrices be thrice the distance between the foci, then eccentricity of ellipse is

A
$1\over2$
B
$2\over3$
✓
$1\over \sqrt 3 $
D
$4\over5$

✓

Answer

Correct option: C.

$1\over \sqrt 3 $

c
(c) According to the condition, $\frac{{2a}}{e} = 6ae$

==> $e = \frac{1}{{\sqrt 3 }}$.

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