Given two symmetric matrices $A,B \in \mathbb{R}^{n\times n}$ which are positive definite, and positive semidefinite respectively.
Can I conclude that
$$x^T(AB)x \ge0, \mbox{for all } x\in \mathbb{R}^n$$
2026-03-24 14:02:53.1774360973
Quadratic Form of the product of two matrices
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