$[ABC]=s \cdot r$ (where s is the semi-perimeter and r is the inradius)
97473
Prove that: area of triangle $S_{ABC}=p \cdot R$, where p is half perimeter of triangle $DEF$
10976
Using induction to prove that $\sum_{r=1}^n r\cdot r! =(n+1)! -1$
113612
Why does $P(\theta_1\mid D, \theta_2) \propto P(D \mid \theta_1, \theta_2)P(\theta_1)$ hold?
78191
Define $\|\cdot\| \colon V \rightarrow \mathbb{R} $ by $\|a\| =\sum 2^n |a_n| $, then choose the correct option
157213
Application of Luca's theorem
111665
How prove this $\{a\}\cdot\{b\}\cdot\{c\}=0$ if $\lfloor na\rfloor+\lfloor nb\rfloor=\lfloor nc\rfloor$
89493
Prove that circumcentre of $ABH,BCH,CAH$ are the vertices of a triangle congruent to $ABC$
115677
Prove the equality of circle's areas
101969
Proof of stars and bars formula
94091
In $ \triangle ABC$ show that $ 1 \lt \cos A + \cos B + \cos C \le \frac 32$
136623
Hints/ Solution in finding a formula $\phi(n)$ for a binary square matrix
46358
geometric interpretation of $\vec v \cdot \operatorname{curl} \vec v = 0 $
84871
Determining the dimension of span$\{AB-BA : A,B \in M_{n \times n}(\mathbb R) \}$
114813
Proof: in $\mathbb{R}$, $((0,1),|\cdot|)$ is not compact.
16517
Arcwise connected part of $\mathbb R^2$
93635
Euclidean geometry in non-inertial frame
111515
Proving that $-a=(-1)\cdot a$