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CAM-Bench-124 is false without symmetry of (A) #1

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@Zshan0

CAM-Bench-124 claims the exact line-search formula $\alpha_k=-(Ax_k-b)^Tp_k/(p_k^TAp_k)$, but neither the informal nor formal statement assumes (A) is symmetric. Counterexample: $A=[[1,1],[0,1]], b=0, x=(0,1), p=(1,0)$. Then $p^TAp=1$ and $\phi(x+\alpha p)=\frac12(\alpha^2+\alpha+1)$, so the minimizer is (-1/2), while the claimed formula gives (-1).

Suggested fix: add $hA_{symm} : A.transpose = A$, or change the numerator to $\frac12(x^TAp+p^TAx)-b^Tp$.

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