question_answer

If \[\mathbf{a}=3\mathbf{i}-\mathbf{j}+2\mathbf{k},\] \[\mathbf{b}=2\mathbf{i}+\mathbf{j}-\mathbf{k}\] and \[\mathbf{c}=\mathbf{i}-2\mathbf{j}+2\mathbf{k},\]then \[(\mathbf{a}\times \mathbf{b})\times \mathbf{c}\] is equal to         

A)          \[24\mathbf{i}+7\mathbf{j}-5\mathbf{k}\]

B)          \[7\mathbf{i}-24\mathbf{j}+5\mathbf{k}\]

C)          \[12\mathbf{i}+3\mathbf{j}-5\mathbf{k}\]

D)          \[\mathbf{i}+\mathbf{j}-7\mathbf{k}\]