ADDITION AND SUBTRACTION OF VECTORS 433 



(1) To find A + B -f C + D 



II -4-330 -5-196 +2-000 



-1-134 



V - 2-500 + 7-000 + 8-000 - 3-464 

 -9-036 



9-036 8 

 -9-109 



. 9-036 



= 82 52' 



(2) TofindA+B-C+D 



H = 4-330 + 5-196 + 2-000 



= 11-526 

 V = 2-500 + 7-000 - 3-000 - 3-464 



= 3-036 



/>= Vll-526 2 + 3-036 2 

 = 11-92 



fl = t - 1 3 ' 036 

 11-526 



- 14 46' 



(3) To find A - B + C - D 



II =4-330 - 5-196 - 2-000 



= -2-866 

 V = 2-500 - 7-000 + 3-000 + 3-464 



- 1-964 



/ = V2-866 2 H- 1-964 2 

 = 3-474 



1-964 



\ 1 . 



= 145 35' 



210. So far the work has been confined to vectors which are in 

 the same plane. In dealing with vectors which are not in the same 

 plane,, the line of action of such a vector must be determined by 

 means of the three angles it makes with the axes OX, OY, and OZ 

 respectively. 



2 E 



