If and are unit vectors satisfying , then is
Answer: 3
Solution
Expanding: .
Since are unit vectors: .
This gives .
Also, , but this should equal 0 for the given condition. So , giving .
Therefore, .
Since are unit vectors: .
This gives .
Also, , but this should equal 0 for the given condition. So , giving .
Therefore, .
JEE Advanced · 2012 · 08 Apr 2012 · Paper 1 · Integer answer