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QUESTION

If $\textbf{c}=\textbf{i}-2\textbf{j},
\textbf{d}=-\textbf{i}+\textbf{j}+3\textbf{k}$ and
$\textbf{e}=\textbf{i}-2\textbf{j}+\textbf{k},$ evaluate
\textbf{c.(d$\times$e)}


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ANSWER

\textbf{c.(d$\times$e)}$=(1,-2,0).(1+6,3+1,2-1)=(1,-2,0).(7,4,1)=7-8+0=-1$




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