99 Percentile Qs Bank for JEE MainMathematicsVector Algebra
If a , b , c are the position vectors of the points A, B, C respectively, then match the items of list-I with those of list-II. The correct match is
Correct answer
3
Step-by-step solution
Given position vectors are O A = a =2 i +3 j +4 k O B = b =3 i +4 j +2 k O C = c =4 i +4 j +2 k O C = c =4 i +2 j +3 k | A B |= 1^2+1^2+2^2 = 6 | B C |= 1^2+2^2+1^2 = 6 and, | C A |= 2^2+1^2+1^2 = 6 Therefore, A B C is an equilateral triangle. B. Given position vectors are O A = a = i +2 j +3 k O B = b =3 i +4 j +7 k O C = c =3 i -2 j -5 k | A B |= 4+4+16 = 24 =2 6 | B C |= 36+36+144 =216=6 6 and | C A |= 16+16+64 = 96 =4 6 | A B |+| C A |=| B C | A, B, C are collinear points. C. Gven position vectors are O A = a =