Question

find the eccentricity of an ellipse of which distance between the foci is 10 and that of focus and corresponding directrix is 15​

Answer 1

ecentricity=e

then

2ae= 10 => ae=5

and

a/e=15.

solving both

we get

e=1/√3

Answer 2

Hii there,

● Answer -

e = 1/√3

● Explanation -

Distance between foci is given by 2ae.

2ae = 10 ...(1)

Distance between focus and corresponding directix is given by a/e.

a/e = 15 ...(2)

Dividing (1) by (2),

(2ae) / (a/e) = 10 / 15

2e² = 2/3

e² = 1/3

Taking square on both sides,

e = 1/√3

Hence, eccentricity of the ellipse is 1/√3.

Thanks dear. Hope this helps you...