\(\, = [(3 \times 4)\,\hat i \times \hat i]\, + \,[2 \times ( - 3)(\hat i \times \hat j) \)
\(+ [(3 \times 4)(\hat k \times \hat k)] + [(3 \times ( - 3)(\hat i \times \hat j)]\)
\( + [(3 \times 4)(\hat i \times k)] + [2 \times 4)(\hat j \times \hat i)] + [(2 \times 4)(\hat j \times k)] \)
\(+ [(3 \times 4)(\hat k \times \hat i)]\, + [(3 \times ( - 3)(\hat k \times \hat j)]\)
\( = 0 + 0 + 0 + ( - 9\hat k) + (12( - \hat j)) + (8( - \hat k)]\, \)
\(+ (8\hat i) + (12\hat j) + [( - 9)( - \hat i)]\)
\( = (8\hat i + 9\hat i) + [ - 12\hat j + 12\hat j]\, + \,[ - 9\hat k + ( - 8\hat k)]\, \)
\(= \,17\hat i + 0\hat j - 17\hat k \)
\(= 17(\hat i - \hat k)\)