các lệnh thêm, thay thế cho latex
$\RR$
——gọi số random tính ———
$!a!x+!b!=0$
Tính a+b = {tinh: !a!+!b!}
++++++++++++++++
Định lý 1 (Định lý về cái gì).
Suppose that $(X,\mathcal M)$ and $(Y,\mathcal N)$ are measurable spaces, and $f:X\to Y$ is a map. We call $f$ is measurable if for every $B\in\mathcal N$ the set $f^{-1}(B)$ is in $\mathcal M$.
$\heva{&x>-1 \\&x>1}\Leftrightarrow x>1$
===
\(\cann{3}{a^{\frac{1}{2}} \cdot \sqrt a } \cdot {a^{\frac{4}{3}}}\)
$\cann{3}{8} = 2$
$\cann{4}{16} = 2$
