iran-konkur 2019 Q136

iran-konkur · Other · konkur-riazi_1398_specialized_new-curriculum Vectors 3D & Lines Vector Algebra and Triple Product Computation
136- For which value of $m$, the three vectors $\vec{a} = (-1,2,3)$, $\vec{b} = (2,\circ,1)$, $\vec{c} = (-4,m,5)$ are coplanar?
(1) $-2$ (2) $2$ (3) $3$ (4) $4$
\textbf{136-} For which value of $m$, the three vectors $\vec{a} = (-1,2,3)$, $\vec{b} = (2,\circ,1)$, $\vec{c} = (-4,m,5)$ are coplanar?

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(1) $-2$ \hfill (2) $2$ \hfill (3) $3$ \hfill (4) $4$

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