12th Class
Mathematics
Sample Paper
Maths Olympiad Model Test Paper-12
question_answer
Let \[\hat{u}\] and \[\hat{v}\] be unit vectors such that \[\hat{u}.\,\hat{v}=0.\] If \[\overrightarrow{r}\] is any vector coplanar with \[\hat{u}\] and \[\hat{v}\], then the magnitude of the vector \[\overrightarrow{r}\times \left( \hat{u}\times \hat{v} \right)\] is _____.