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QUESTION

If ${\bf c}={\bf i}-{\bf j}+2{\bf k}$  and ${\bf d}={\bf j}-{\bf
k}$  find $\mathbf{c\times d}$.

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ANSWER


$\mathbf{c\times d}=(1,-1,2)\times(0,1,-1)
=(-1(-1)-2(1),2(0)-1(-1),1(1)-(-1)0)$

$\hspace{0.2in}=(1-2,0+1,1-0)=(-1,1,1)$



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