Moment of Three Vector forces about a Point O and its Resultant (solved example)

Hi,

Problem: 

Determine the resultant moment about the fixed end at joint O.

F1 = (-60i + 40j +20k) lbs

F2 = (80i + 40j -30k) lbs

F3 = (40i + 20j - 15k) lbs

A) Show all steps using Cartesian Vector Notation.

B) Show all steps using Scalar Notation.

C) Show the final orientation of the MO on a sketch.

Solution:

If you have any doubt, please leave a comment below.

Thanks!