Let A(x1,y1,z1) and B(x2,y2,z2) be two arbitrary points in three–dimensional space.
(i) Define the position vector of a point with respect to the origin O(0,0,0).
(ii) Express the vector AB in component form in terms of x1,y1,z1 and x2,y2,z2.
(iii) Hence show that the magnitude ∣AB∣ equals (x2−x1)2+(y2−y1)2+(z2−z1)2.