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QUESTION Which of the following sets of vectors form a basis for
$\textbf{R}^3$?

\begin{description}

\item[(a)]
$(2,3,4),(1,-4,7),(3,9,-2);$

\item[(b)]
$(3,2,4),(2,6,-3),(12,-5,0);$

\item[(c)]
$(1,23,11),(2,5,-4),(0,41,26).$

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ANSWER
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\item[(a)]
spans

\item[(b)]
spans

\item[(c)]
no - the vectors are of the form $\textbf{a,b,2a-b}$.

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