Crey | Let the superscript T represent the transpose operation. Consider the function f ( x ) = 1 2 x T Q x − r T x , where x and r are n × 1 vectors and Q is a symmetric n × n matrix. the stationery point of f(x) is Q, Q-1r, r r T r , r

Question

Let the superscript T represent the transpose operation. Consider the function $f (x) = \frac{1}{2} x^{T} Q x - r^{T} x$ , where x and r are n × 1 vectors and Q is a symmetric n × n matrix. the stationery point of f(x) is

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