in the x, y and z directions respectively. The resultant of is the A A1iˆ, A2 and A3kˆ ˆj    vector so that A A1iˆ A2 A3kˆ A ˆj The magnitude of is    . In particular, the position vector or radius A A A12 A22 A32 (x, y, z) vector from O to the point is written as r    r xiˆ yˆj zkˆ 7
A in the x, y and z directions respectively. The resultant of A1iˆ, A2 ˆj and A3kˆ is the vector A so that A  A1iˆ  A2 ˆj  A3kˆ The magnitude of A is A  A12  A22  A32 . In particular, the position vector or radius vector r from O to the point (x, y, z) is written as r  xiˆ  yˆj  zkˆ 7