Mathematics for IGCSE & O level - Vectors (Section 2 - No. 8)
Given \(\vec{u} = \begin{pmatrix} 2 \\ -1 \end{pmatrix}\) and \(\vec{w} = \begin{pmatrix} -1 \\ 3 \end{pmatrix}\), calculate \(2\vec{u} + \vec{w}\).
\(\begin{pmatrix} 3 \\ 1 \end{pmatrix}\)
\(\begin{pmatrix} 5 \\ 1 \end{pmatrix}\)
\(\begin{pmatrix} 3 \\ -5 \end{pmatrix}\)
\(\begin{pmatrix} -5 \\ 5 \end{pmatrix}\)
Объяснение
2u + w = 2\(\begin{pmatrix} 2 \\ -1 \end{pmatrix}\) + \(\begin{pmatrix} -1 \\ 3 \end{pmatrix}\) = \(\begin{pmatrix} 4 \\ -2 \end{pmatrix}\) + \(\begin{pmatrix} -1 \\ 3 \end{pmatrix}\) = \(\begin{pmatrix} 3 \\ 1 \end{pmatrix}\)