Two vectors are given by A=2i^−j^+kk^ and B=ki^+2j^+3k^, where k is a real number.
(i) Write the mathematical condition for the two vectors to be perpendicular.
(ii) Determine all possible values of k that satisfy the condition obtained in part (i).
(iii) For each value of k found in part (ii), calculate the magnitude of the vector product A×B and state the direction of A×B with respect to A and B. Comment on how your results in parts (i) and (iii) are consistent with the geometrical meaning of the products involved.