Maths-
General
Easy
Question
The sum of distances of any point on the ellipse 3 x2 + 4y2 = 24 from its foci is
- 8
- 4
- 16
- none of these
Hint:
The sum of the distances to any point on the ellipse (x,y) from the two foci (c,0) and (-c,0) is a constant. That constant will be 2a. If we let d1 and d2 bet the distances from the foci to the point, then d1 + d2 = 2a.
The correct answer is: 4
Given :
Dividing both sides by 24, we get
The sum of the distances to any point on the ellipse (x,y) from the two foci (c,0) and (-c,0) is a constant. That constant will be 2a. If we let d1 and d2 bet the distances from the foci to the point, then d1 + d2 = 2a.
d1 + d2 = 2a
d1 + d2 = 2
d1 + d2 = 4
Thus, the sum of distances of any point on the ellipse 3 x2 + 4y2 = 24 from its foci is 4.
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