Mathematics for IGCSE & O level - Vectors (Section 2 - No. 23)
If \(\vec{a} = \begin{pmatrix} 2 \\ -1 \end{pmatrix}\), and \(\vec{b} = \begin{pmatrix} -1 \\ 3 \end{pmatrix}\), what is the magnitude of \(\vec{a} + \vec{b}\)?
\(\sqrt{5}\)
\(\sqrt{10}\)
5
10
ব্যাখ্যা
a + b = \(\begin{pmatrix} 2 \\ -1 \end{pmatrix}\) + \(\begin{pmatrix} -1 \\ 3 \end{pmatrix}\) = \(\begin{pmatrix} 1 \\ 2 \end{pmatrix}\). Magnitude = sqrt(1^2+2^2)= sqrt(5)