$\max \ (x^TAx+y^TAy)$ such that $x^Tx = y^Ty = 1$ and $x^Ty = 0$
62958
Maximize $\mathrm{tr}(Q^TCQ)$ subject to $Q^TQ=I$
113255
$X,Y\sim U(0,1)$ are independent, $W=\max (X,Y)$.
7813
In a complex vector space, $\langle Tx,x \rangle=0 \implies T = 0$
106827
Proof for two sequences producing the maximum value when sorted
41619
How find the maximum value of $|bc|$
3885
Maximum and minimum of of $f(x)=|x-1|+|x-2|+|x-3|$
46265
Minimal polynomial of the operator $T:V\oplus W\to V\oplus W$
72920
$x \perp y$ if and only if $\Vert x + \alpha y \Vert \ge \Vert x \Vert$ for all scalars $\alpha$
143765
To Show that $\exp(tX)\exp(tY)= \exp(t(X+Y)) + (1/2)t^2[X, Y] +o(t^3)$
147888
Show that $M=\bigcap_{\mathfrak{p}\in\operatorname{Spec}(R)}M_\mathfrak{p}=\bigcap_{\mathfrak{m}\in\text{Max}(R)}M_\mathfrak{m}$ for certain $M$.
143374
Elegant proof that maximum of sums is, at most, sum of maximums
119032
Is ${\bf x^TAx} \ge { a \bf x^Tx}$ for some $a>0$ not dependent on $\bf x$ if $\bf A$ is positive definite matrix?
61472
If $0<x<y$, then prove that $\sqrt{x} <\sqrt{y}$ and $x <\sqrt{xy} <y$
128440
If $X_1,\ldots,X_n\sim Uniform(0,1)$ and $Y=\max[X_1,\ldots,X_n]$, find $E(Y)$
127242
$|A\times B|= \text{max}(|A|,|B|)$ for infinite sets
11824
A maximization problem
57096
Show that $\max{\{|a|+|b|,|c|+|d|\}} \leq \max{\{|a|,|c|\}}+\max{\{|b|,|d|\}}.$