For some $c \geq 0$ $\text{sup} \ \{ c \cdot f(x): \text{some domain of $x$} \}$ = $c \cdot \text{sup} \ \{f(x): \text{same domain of $x$} \}$
100565
Property of sup of a set of numbers
79367
Understanding the difference between two theorems related to $|G\,:\,K|=|H\,:\,K|\cdot|G\,:\,H|$.
6450
Show $\mathbb{E}[f(X)g(X)] \geq \mathbb{E}[f(X)]\mathbb{E}[g(X)]$ for $f,g$ bounded, nondecreasing
148954
Understanding a statement about equivalent norms ($||\cdot ||_2 \sim||\cdot||_1 $)
52642
Show that $\text{C}/c \cong (c/(\text{C}^{\text{op}}))^{\text{op}}$
50273
How to prove $\lvert \lVert x \rVert - \lVert y \rVert \rvert \overset{\heartsuit}{\leq} \lVert x-y \rVert$?
153069
Proof for Unique Factorization Domain
72920
$x \perp y$ if and only if $\Vert x + \alpha y \Vert \ge \Vert x \Vert$ for all scalars $\alpha$
141078
Domain over which a polynomial is strictly positive
153191
A function satisfy $x\frac{\partial f(x,y)}{\partial x}+y\frac{\partial f(x,y)}{\partial y}=0$ in a convex domain implies it is a constant
156235
Are $x \cdot 0 = 0$, $x \cdot 1 = x$, and $-(-x) = x$ axioms?
139019
Polynomial satisfying $f(x) = f'(x) \cdot f''(x)$
122330
Prove that there exists some $c\in(-3,3)$ such that$ \ \ g(c) \cdot g''(c)<0$.
56413
$f(g(x))=g(f(x))$ implies $f(c)=g(c)$ for some $c$
126698
measurability of a function -equivalent conditions
113152
Prove Principal Ideal Domain from Bezout's condition, and terminating divisibility chain
96132
$R$ integral domain : $u\in R^*, a \text{ is prime} \iff au \text{ is prime}$