Question
An ellipse has OB as a semi – minor axis, F, F' are its foci and the angle FBF' is a right angle. Then the eccentricity of the ellipse is
- none of these
Hint:
Eccentricity of ellipse formula is given by
The correct answer is:
m1m2 = -1
Eccentricity of ellipse formula is given by
From equation (1)
Thus, the eccentricity of the ellipse is
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