If the angle between the straight lines joining the foci and the ends of the minor axis of the ellipse…
- $1 / 2$
- $1 / 4$
- $1 / 3$
- $1 / \sqrt{2}$
Solution

Apply pythagoras theorem, in $\Delta A S_1 S_2$ $\left(S_1 A\right)^2+\left(A S_2\right)^2=\left(S_1 S_2\right)^2$ $a^2+a^2=(2 a e)^2$ $\Rightarrow \quad 2 a^2=4 a^2 e^2$ $\therefore \quad e=\frac{1}{\sqrt{2}}$
Asked in: AP EAMCET 2022 (05 Jul Shift 1)