The number of vectors of unit length perpendicular to vectors ` vec a=(1,1,0)a n d vec b=(0,1,1)` is a. one b. two c. three`` d. infinite

Options

A. one
B. two
C. three
D. infinite

Answer

b

Explanation

we know that if `hatn` is perpendicular to `veca` as we as `vecb` .then
`hatn=(vecaxxvecb)/(|vecaxxvecb|)or (vecbxxveca)/(|vecbxxveca|)`
As ` veca xx vecb and vecb xx veca` represent two vectors in opposite directions , we have two possible value of `hatn`.