JEE Main 2012 — Three Dimensional Geometry Question with Solution
JEE Main 2012 (12 May Online)
Question
A unit vector which is perpendicular to the vector and is coplanar with the vectors and is
Choose an option
Show full solutionCorrect option: D
Correct answer
D
Step-by-step explanation
Let be the required unit vector.
Since is perpendicular to .
Since vector is coplanar with the vector and .
where and are some scalars.
Now from equation (i),
Since vector is a unit vector, therefore
When , then ,
When , then ,
Here required unit vector is or .
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This is a previous-year question from JEE Main 2012, covering the Three Dimensional Geometry 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.