Find the equation of an ellipse whose foci are centre is at origin and which passes through the point (4, 1).
Show that the locus of a point which moves so that the sum of its distances from two points is equal to 6, is an ellipse whose eccentricity is
Let the point be .
The fixed points are A (4, 0), B (-4, 0). The given condition is :
PA - PB = 2
Squaring both sides, we get
Squaring again, we get
Hence, the locus of point P is
which is the standard form of hyperbola in the form .