Problem
Two forces A and B are acting at one point. Determine the resultant.
Force A is 10 N and Force B is 6 N.
Solution
using law of cosines and law of sines:
R2 = (10 N)2 + (6 N)2 - 2(10 N)(6 N) cos 155°
R = 15.64 N
Its angle from the horizontal axis (γ) is:
γ = sin-1[((sin 155°)/15.64)*10] + 15°
γ = 30.68°