The magnitude of two vectors which can be represented in the form `i+j+(2x)k` is `sqrt(18)`. Then the unit vector that is perpendicular to these two vectors is

Options

A. `(-i+j)/(sqrt(2))`
B. ` (i - j )/(8sqrt(2))`
C. ` (-i + j )/8 `
D. `(-i + j)/(2sqrt(2))`

Answer

A

Explanation

`hat(n) = (vec(A) xx vec(B))/(|vec(A) xx vec(B)|)`