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If\(V= \begin{pmatrix} -2\\ 4\end{pmatrix}\) and \(U= \begin{pmatrix} -1\\ ...

If \(V = \begin{pmatrix} -2 \\ 4 \end{pmatrix}\) and \(U = \begin{pmatrix} -1 \\ 5 \end{pmatrix}\), find \(|U + V|\).
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  • A \(3\sqrt{10}\)
  • B \(\sqrt{82}\)
  • C 15
  • D \(2\sqrt{5}\)
Correct Answer: Option A
Explanation:
\(V = \begin{pmatrix} -2 \\ 4 \end{pmatrix}\) and \(U = \begin{pmatrix} -1 \\ 5 \end{pmatrix}\)
\(U + V = \begin{pmatrix} -1 - 2 \\ 5 + 4 \end{pmatrix} = \begin{pmatrix} -3 \\ 9 \end{pmatrix}\)
\(|U + V| = \sqrt{(-3)^{2} + 9^{2}} = \sqrt{9 + 81} = \sqrt{90}\)
= \(sqrt{9 \times 10} = 3\sqrt{10}\)

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