An ellipse has `O B` as the semi-minor axis, `Fa n dF '` as its foci, and `/_F B F '` a right angle. Then, find the eccentricity of the ellipse.

B is extermity of the minor axis of an elipse whose foci are S and S'. If angle SBS' is a right angle, then the eccfentricity of the ellipse is

If OB is the semi-minor axis of an ellipse, F_1 and F_2 are its foci and the angle between F_1B and F_2B is a right angle, then the square of the eccentricity of the ellipse is

If the lines joining the foci of an ellipse to an end of its minor axis are at right angles , then the eccentricity of the ellipse is e =

Let S and s' be the foci of an ellipse and B be one end of its minor axis . If SBS' is a isosceles right angled triangle then the eccentricity of the ellipse is

If the length of the minor axis of an ellipse is equal to half of the distance between the foci then the eccentricity of the ellipse is

Pa n dQ are the foci of the ellipse (x^2)/(a^2)+(y^2)/(b^2)=1 and B is an end of the minor axis. If P B Q is an equilateral triangle, then the eccentricity of the ellipse is 1/(sqrt(2)) (b) 1/3 (d) 1/2 (d) (sqrt(3))/2