Find the eccentricity of an ellipse whose latus rectum is one half of its minor axis.

Let the equation of the required ellipse is
…(i)
It is given that,
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We know that,
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and Length of Minor Axis = 2b
So, according to the given condition,
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⇒ 2b = a …(ii)
Now, we have to find the eccentricity
We know that,
…(iii)
where, c2 = a2 – b2
So, c2 = (2b)2 – b2 [from (ii)]
⇒ c2 = 4b2 – b2
⇒ c2 = 3b2
⇒ c = √3b2
⇒ c = b√3
Substituting the value of c and a in eq. (iii), we get
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