We present an example of smooth quasi-convex functions in the positive octant of R3\mathbb{R}^3 which cannot be obtained as the images of convex smooth functions under a monotone smooth mapping of R\mathbb{R}.

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Nicolai V. Krylov

127 Vincent Hall, University of Minnesota, Minneapolis, MN 55455, U.S.A.

nkrylov@umn.edu
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N. V. Krylov. “A Note on Quasi-Convex Functions.” Journal of Convex Analysis 26 (2019), No. 1, 269–273. https://doi.org/10.68381/jca26015