A sphere is the locus of a point in a three-dimensional space, which remains at a constant distance from a fixed point. The fixed point is called the Center of the sphere and the constant distance is called the radius of the sphere.
Let be the position vector of any point P(x, y, z) on the surface of a sphere with respect to the origin O. Let the position vector of the center C(c1, c2, c3) be . Thus,
If be the radius of the ...