JEE Main 2018PhysicsMathematics in PhysicsEasyMCQ

JEE Main 2018 — Mathematics in Physics Question with Solution

JEE Main 2018 (16 Apr Online)

Question

Let A→=i^ + j^ and B→=(2i^- j^) . The magnitude of a coplanar vector C→ such that A→ . C→=B→. C→= A→ . B→ is given by:

Choose an option

Show full solutionCorrect option: C
Correct answer
C59

Step-by-step explanation

If C→=ai^ + bj^ then, 
A→ . C→=A→ . B→  
a+b=1  .......(i)
B→. C→= A→ . B→
2a-b=1  ......(ii)
solving equations (i) and (ii) we get, 
a=13, b=23
C→= 19+49= 59

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About this question

This is a previous-year question from JEE Main 2018, covering the Mathematics in Physics chapter of Physics. 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.