Mid-point convexity does not imply convexity
20614
Example of a function such that $\varphi\left(\frac{x+y}{2}\right)\leq \frac{\varphi(x)+\varphi(y)}{2}$ but $\varphi$ is not convex
16463
Is the function $\mbox{tr}(XAX')$ convex?
150727
Characterization convex function.
102350
Cost function of neural network is non-convex?
119735
Show that $\mathbb{E}(g(T-p)) < \mathbb{E}(g(S-p))$ for any convex function $g$ if $T$ and $S$ are estimators of $p$
48490
Examples of $f$ strictly convex, either with one minimizer or with no minimizer.
87207
Prove that the support function of an arbitrary set $A\subset\mathbb R^n$ is convex
141505
KKT points and nonlinear optimality (theory)
86305
A secant inequality for convex functions
125175
convexity proof of a function including ln and sums
24230
Proof that CRF models and logistic models are convex functions
60521
Continuity of a convex function
67313
Proving $\{(x_1, x_2) \in \mathbb{R}^2_{+} \mid x_1 x_2 \geq 1\}$ is convex
5076
Minimize Function over Convex Subset
140383
Concave implies subadditive
135867
$f(x)=x^3$ is convex nor concave without to derivate
94231
Prove that a non-empty closed convex $S$ has an extreme point iff it does not contain any line