JEE Main 202622 JanuaryEvening Shift
- Exam
- JEE Main
- Year
- 2026
- Date
- 22 January
- Shift
- Evening Shift
- Subject
- Mathematics
- Chapter
- Ellipse
JEE Main 2026 · 22 January · Evening Shift · Mathematics · Ellipse
Let S and S^ be the foci of the ellipse x^ 2 25 + y^ 2 9 =1 and...
Let S and be the foci of the ellipse and be a point on the ellipse in the first quadrant. If , then is equal to :
Options
- A15
- B11
- C17
- D13
Correct answer
D. 13
Step-by-step solution
For the ellipse , we have , , .
So foci are at .
For point on the ellipse: .
Given
Let and .
From , we get .
Substituting into the given equation: , so .
Thus .
From and , subtracting gives , so .
From the ellipse equation: .
Therefore .
So foci are at .
For point on the ellipse: .
Given
Let and .
From , we get .
Substituting into the given equation: , so .
Thus .
From and , subtracting gives , so .
From the ellipse equation: .
Therefore .