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QUESTION

Write down the vector equation of the straight line which passes
through the two points $A(1,2,-1)$ and $B(0,1,-3)$.

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ANSWER

$A(1,2,-1),\
B(0,1,-3)\hspace{1cm}\vec{AB}=(0-1,1-2,-3+1)=(-1,-1,-1)$

The equation of the line is $\textbf{r}=(1,2,-1)+t(-1,-1,-2)$




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