I understand from this post: How can we show/prove that a rank-$1$ matrix is non-convex? that a rank-1 matrix is non convex but I don't understand the proof. I know that the summation of two convex functions should be convex but why are we summing the ranks of two matrices? Can I treat the rank of a matrix $X$ as a function $(f(X))$? I would appreciate it if someone would explain to me how summing the rank is a valid test for testing the convexity of a rank-1 matrix?
2026-02-23 12:34:37.1771850077
Explaining the non convexity of rank 1 matrix
192 Views Asked by Bumbble Comm https://math.techqa.club/user/bumbble-comm/detail AtRelated Questions in LINEAR-ALGEBRA
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