JEE MainMathematicsEllipse
Let the length of the latus rectum of the ellipse x^2 36 + y^2 k ^2 = 1 , where 0 0 ) intersects the x -axis and y -axis at the points A and B , respectively. If the area of the circle having the line segment AB as a diameter is 25 , then the value of 2 + , where ( , ) is the centre of the circle, is equal to
Options
- A55
- B10
- C14
- D11
Correct answer
D. 11
Step-by-step solution
The equation of the ellipse is x^2 36 + y^2 k ^2 = 1 . Since 0 The length of the latus rectum is given by 2b^2 a = 3 . Substituting the values, we get 2 k ^2 6 = 3 k ^2 = 9 . Since k > 0 , we have k = 3 . The equation of the line L becomes 3x + 4y = . The points of intersection with the axes are A ( 3 , 0 ) and B (0, 4 ) . The length of the line segment AB is the diameter of the circle. Area of the circle = r^2 = 25 r = 5 . Thus, the diameter AB = 10 . Using the distance formula for AB : AB ^2 = ( 3 )^2 + ( 4 )^2 =