The eccentricity of the ellipse 
if its latus - rectum is equal to one half of its minor axis, is
Given that we need to find the eccentricity of the ellipse whose latus - rectum is one half of the minor axis.
We know that length of latus rectum is 
and length of minor axis is 2b.
⇒ 
⇒ a = 2b.
We know that eccentricity of the ellipse is 
⇒ 
⇒ 
⇒ 
∴ The correct option is A
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