Duncle.com physical sciences (mathematical methods of physics unit vector n on the xy plane is at an angle of 120° with respect to . the angle between vectors ū

duncle.com Physical Sciences (Mathematical Methods of Physics unit vector n on the xy plane is at an angle of 120° with respect to . The angle between vectors ū=ai + bń and v = añ +bj will be 60° if at+h VaA v on tb (A) b=V3a/2 (B) b 2a/3 (C) b a/2 (D) b= a C) üv =ū|| v| cos 60 a (in+b (ni)+ab + ba va +b +2ab cos 120 a +b? +2ab cos120 a2 cos 120° b2 cos 1209+ ab + ba =a+bab 2a2 5ab +262 0 a =Or b 2 how that 1/2 came.can you please explain step by step