JEE Main 2015MathematicsVector AlgebraMediumMCQ

JEE Main 2015 — Vector Algebra Question with Solution

JEE Main 2015 (04 Apr)

Question

Let a→, b→  and  c→ be three non - zero vectors such that no two of them are collinear and a→×b→×c→=13b→c→a→. If θ is the angle between vectors b→ and c→, then a value of sinθ is 

Choose an option

Show full solutionCorrect option: B
Correct answer
B 2 2 3

Step-by-step explanation

Given a→ × b→ × c→= 13 b→ c→a→

a→⋅c→ b→- b→⋅c→ a→=13 b→c→ a→

⇒ a→⋅c→=0  and  b→⋅c→= -13 b→c→

b→c→cosθ= -13 b→c→

cosθ= -13

sinθ= 1-19= 89 = 223

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About this question

This is a previous-year question from JEE Main 2015, covering the Vector Algebra chapter of Mathematics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.