posted by Arielle on .
Forces of 675 lb and 828 ob act on a body. The smaller force acts due north; the larger force acts N 52.3 degrees E. Find the direction and the magnitude of the resultant.
Set 'em up and knock 'em down:
use the law of cosines to find the resultant r:
r^2 = 675^2 + 828^2 - 2(675)(828)cos(180-52.3)
Having r now, you can use the law of sines to get the resultant angle a:
r/sin(180-52.3) = 828/sin a
where a is measured in degrees east of north.