Math Chapter Wise Operations On Vectors English MCQ UKPSC Lecturer (Mains) 2020 Q.If a b c 0 + + = and a 3, b 5, c 7 =, then the angle between a and b is: A1 2 cos 15 − B1 11 cos 14 − C1 47 cos 40 − D1 1 cos 2 − Show answer Correct answer: 1 1 cos 2 −