Two forces of the same magnitude act at a point.the square of their resultant is 3 times the product of their magnitudes.the angle between them is?

Answer 1

consider the resultant of the two forces with the law of cosines

c^2=a^2+b^2-2abcosTheta
but a=b, so one has...

3a^2=2a^2-2a^2cosTheta

costheta=1/2
theta=arccos (1/2)

check all that.