JEE Main 2005Annual, Paper 1MathematicsMediumCoordinate Geometry478× since 2002An ellipse has OBOBOB as semi minor axis, FFF and FFF' its focii and theangle FBFFBFFBF' is a right angle. Then the eccentricity of the ellipse is :AOption A. 12{1 \over {\sqrt 2 }}21BOption B. 12{1 \over 2}21COption C. 14{1 \over 4}41DOption D. 13{1 \over {\sqrt 3 }}31CheckSkip · show solution
