Question

The sum of focal distances of a point on the ellipse `x^(2)/4+y^(2)/9=1` is:
A. 4 units
B. 6 units
C. 8 units
D. 10 units

Answer 1

Correct Answer - A
Given equation of ellipse is
`x^(2)/36+y^(2)/16=1`
This is an ellipse.
`rArr" "x^(2)/((2)^(2))+y^(2)/((3)^(2))=1`
`rArr" "a=2" and "b=3`
Length of major axis = 2a = 4
Since, we have
Sum of the focal distances of a point on ellipse = length of major axis.
`:." Required Ans = 4 units.