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nonconvexcard

A convex problem with a duality gap

ProofAdvanced⏱ 30 minAdvanced Optimizationduality gapslatercounterexample

Problem

Consider

min⁡x,y e−xsubject tox2y≤0,y>0.\min_{x,y}\ e^{-x} \quad\text{subject to}\quad \frac{x^2}{y}\le0,\quad y>0 .

Show that the problem is convex, compute p⋆p^\star and d⋆d^\star, and identify which hypothesis of Slater's theorem fails.

Write a complete argument. Every inequality you use should be one you could state precisely.

Solution

Opening this before you have a real attempt on paper is the fastest way to feel like you understand something you cannot reproduce.

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