Convexity of the set with the fixed norm
40438
Proving that closed (and open) balls are convex
66151
Solving inequality for convex functions.
28511
Hypervolume of a $N$-dimensional ball in $p$-norm
16943
Midpoint-Convex and Continuous Implies Convex
15491
Prove that $f:\mathbb R^n\to\mathbb R$ is affine if and only if it is convex and concave
46435
2-norm of the orthogonal projection
22689
Reference for trace/norm inequality
25738
Jensen's Inequality implies convexity?
125175
convexity proof of a function including ln and sums
138959
On the equality case of the Hölder and Minkowski inequalities
86643
Convex function almost surely differentiable.
106718
Prove if C is midpoint convex and closed then its a convex set
143869
Showing that the norm of the canonical projection $X\to X/M$ is $1$
139272
On the norm of a quotient of a Banach space.
143936
Show that $f(x)=||x||^p, p\ge 1$ is convex function on $\mathbb{R}^n$
60887
$d_A(x) = \inf_{a \in A} \|x-a\|$ is convex if and only if $A$ is convex
122305
Proof of matrix norm property: submultiplicativity