The parametric equations of an ellipse are given by the following relations:                                 That is, (x 2 /a 2 ) + (y 2 /b 2 ) = 1; where a and b are known as semi-major axis and...

The parametric equations of an ellipse are given by the following relations:

That is, (x
²
/a²
) + (y
²
/b²
) = 1; where a and b are known as semi-major axis and semi-minor axis respectively. The eccentricity of the curve is given by the relation:

For a = 2, and b = 1.

Prove, by taking at least five points, the sum of radial distances of any point on the curve from the two foci always remains the same. What is the numerical value of this distance?