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Linear AlgebraSuperchallengeOrthogonality & Least Squares

Orthogonality & Least Squares · Superchallenge problem

For a nonzero vector w∈R6\mathbf w \in \mathbb R^6 let Hw=I−2 wwTwTwH_{\mathbf w} = I - \dfrac{2\,\mathbf w\mathbf w^{T}}{\mathbf w^{T}\mathbf w} be the reflection across the hyperplane orthogonal to w\mathbf w. With u=(1,0,0,0,0,0)\mathbf u = (1, 0, 0, 0, 0, 0) and v=(1,1,1,1,0,0)\mathbf v = (1, 1, 1, 1, 0, 0), find tr⁡((HuHv)2026)\operatorname{tr}\big((H_{\mathbf u}H_{\mathbf v})^{2026}\big).