Question

what is the angle between A vector and the resultant of (A+2Bcap) and (2A-2Bcap)​

Answer 1

Answer:

R=a2+b2+2abcosθ

10A=(2A)2+2A2)+2(2A)(2A)cosθ

10A2=4A+2A2+42A2cosθ

10=6+42cosθ

cosθ=(424)=(21)

∴θ=(4π)