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Linear AlgebraHardSingular Values & the SVD

Singular Values & the SVD · Hard problem

Let A=(120202)A = \begin{pmatrix}1 & 2 & 0\\2 & 0 & 2\end{pmatrix}. The maximum of ∥Ax∥\|Ax\| over unit vectors x∈R3x \in \mathbb R^3 is attained at x=±v1x = \pm v_1, the first right singular vector. Taking the sign with positive first component, find the sum of the three components of v1v_1. Give your answer in simplest radical form.