Question

The equation of the locus of a point which moves such that its difference of distances from the points (3,0) and (-3,0) is 4 units is given by

Answer 1

Let P(x,y) be the point which moves such that sum of the distance from F(3, 0) as well as F’(3,0) is 9.

The curve traced by P is an ellipse length of whose major axes ( 2a=4) and whose central is at the midpoint of FF’ at (0,0) where F, F’ are the foci. Ae=3 and a = 4/2 = 2. E=3/2.