Let and be three given vectors. If is a vector such that and , then the value of is
Answer: 9
Solution
From , we have , so is parallel to .
Thus for some scalar .
Using :
Computing:
So:
Thus:
Finally:
Thus for some scalar .
Using :
Computing:
So:
Thus:
Finally:
JEE Advanced · 2011 · 10 Apr 2011 · Paper 2 · Integer answer