Let a̅, b̅ and c̅ be three mutually perpendicular vectors each of unit magnitude.
If A̅ = a̅ + b̅ + c̅, B̅ = a̅ – b̅ + c̅ and C̅ = –a̅ + b̅ + c̅, then which one of the following is correct ?

Mathematics 2018 NDA Mathematics 2018 NDA 2018

Options