Home
Class 11
MATHS
If S\ a n d\ S ' are two foci of the ell...

If `S\ a n d\ S '` are two foci of the ellipse `(x^2)/(a^2)+(y^2)/(b^2)=1\ a n d\ B` is and end of the minor axis such that `"Delta"B S S '` is equilateral, then write the eccentricity of the ellipse.

A

`3/4`

B

`7`

C

`4/5`

D

`1/2`

Text Solution

Verified by Experts

The correct Answer is:
`1/2`

For ellipse `frac(x^(2))(a^(2))+frac(y^(2))(b^(2))=1`, distance between foci is `2ae`, where e is eccentricity of an ellipse.
So, 2 ae will be length of side of equilateral triangle `triangle BSS’`
And semi minor axis will be height of this triangle.
We know that height of equilateral triangle is `frac(sqrt(3))(2)` time s its side.
So, According to given condition, `b=frac(sqrt(3))(2) 2ae`
...
Doubtnut Promotions Banner Mobile Dark
|

Topper's Solved these Questions

  • DERIVATIVES

    RD SHARMA|Exercise Solved Examples And Exercises|236 Videos
  • FUNCTIONS

    RD SHARMA|Exercise Solved Examples And Exercises|157 Videos

Similar Questions

Explore conceptually related problems

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

S and T 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 STB is an equilateral triangle,the eccentricity of the ellipse is e then find value of 4e

Knowledge Check

  • Let S and T be the foci of the ellipse (x^(2))/(a^(2))+(y^(2))/(bh^(2)) = 1 and be an end of the minor axis. If STB is an equilateral triangle, then eccentricity of the ellipse is

    A
    `1/4`
    B
    `1/3`
    C
    `1/2`
    D
    `sqrt(3/2)`
  • S and T 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 STB is equilateral triangle, then eccentricity of the ellipse is

    A
    `1/4`
    B
    `1/3`
    C
    `1/2`
    D
    `sqrt(3/2)`
  • S and T are foci of an ellipse and B is an end of the minor axis , if STB is an equilateral triangle , the eccentricity of the ellipse , is

    A
    `1//4`
    B
    `1//3`
    C
    `1//2`
    D
    `2//3`
  • Similar Questions

    Explore conceptually related problems

    The normal at an end of a latus rectum of the ellipse (x^2)/(a^2)+(y^2)/(b^2)=1 passes through an end of the minor axis if:

    Let S and S' be two foci of the ellipse (x^(2))/(a^(3))+(y^(2))/(b^(2))=1. If a circle described on SS' as diameter intersects the ellipse at real and distinct points,then the eccentricity e of the ellipse satisfies c=(1)/(sqrt(2))( b) e in((1)/(sqrt(2)),1)e in(0,(1)/(sqrt(2)))(d) none of these

    The normal at an end of a latus rectum of the ellipse (x^(2))/(a^(2))+(y^(2))/(b^(2))=1 passes through an end of the minor axis if

    S and S' are the foci of an ellipse and B is an end of the minor axis. If SS' B is an equilateral triangle, the eccentricity of the ellipse is.

    If S and S' are two foci of an ellipse (x^2)/(a^2) + (y^2)/(b^2) = 1 (a lt b) and P(x_1, y_1) a point on it, then SP +S' P is equal to