Find a Vector of Magnitude 171 Which is Perpendicular to Both of the Vectors a = ^ I + 2 ^ J 3 ^ K and a = ^ I + 2 ^ J 3 ^ K .

Question

Find a vector of magnitude [\sqrt{171}] which is perpendicular to both of the vectors [\vec{a} = \hat{ i } + 2 \hat{ j } - 3 \hat{ k } ] and [\vec{a} = \hat{ i } + 2 \hat{ j } - 3 \hat{ k } ] .