A line segment joining (1, 0, 1) and the origin (0, 0, 0) is revolved about the x-axis to form a right circular cone. If (x, y, z) is any point on the cone other than the origin, then it satisfies the equation
x2−y2−z2=0
Let A be the point (1,0,1) and P(x, y, z) be any point on the cone obtained revolving OA about the x-axis.
From the figure,
ΔOPM and ΔOAC are similarOPOA=OMOC√x2+y2+z2√2=x1⇒x2+y2+z2=2x2⇒x2−y2−z2=0