Question

Let a be the position vector of a given point (X1,Y 1, 21), and r the position vector of any point (x, y, z). Describe the locus of r if (a) lr -al = 3, (b) (r-a). a = 0, (c) (r -- a) •p = 0.
Ans. (a) Sphere, center at (x1.71,21) and radius 3.
(6) Plane perpendicular to a and passing through its terminal point.
(c) Sphere with center at (x,/2, 77/2, z,/2) and radius vz?+ yž
2
+
2
or a sphere with a as diameter.
Gion 1h​

Answer 1

Answer:

55.........................