Two vectors ¯a and ¯b are at an angle of 600 with each other. Their resultant makes an angle of 450 with ¯a . If |¯b| =2 units, then |¯a| is
√3
√3−1
√3+1
√3/2
tan 450=2sin600a+2cos600=√3a+1or 1=√3a+1or a+1=√3or a=√3−1