Відмінності між версіями «Формули MS Word MathType»

(Нова сторінка: <math> \operatorname{erfc}(x) = \frac{2}{\sqrt{\pi}} \int_x^{\infty} e^{-t^2}\,dt = \frac{e^{-x^2}}{x\sqrt{\pi}}\sum_{n=0}^\infty (-1)^n \frac{(2n)!}{n!(2x)^{2n}} </...)
 
Рядок 4: Рядок 4:
 
   \frac{e^{-x^2}}{x\sqrt{\pi}}\sum_{n=0}^\infty (-1)^n \frac{(2n)!}{n!(2x)^{2n}}
 
   \frac{e^{-x^2}}{x\sqrt{\pi}}\sum_{n=0}^\infty (-1)^n \frac{(2n)!}{n!(2x)^{2n}}
 
</math>
 
</math>
 +
 +
<wikitex>
 +
Let $Q$ be any finite set, and $\mathcal B=2^Q$ be the collection of the subsets of
 +
$Q$. Let $f:\mathcal B\rightarrow \mathbb R$ be a function assigning real numbers to
 +
the subsets of $Q$ and suppose $f$ satisfies the following conditions:
 +
:(i) $f(A)\ge 0$ for all $A\subseteq Q$, $f(\emptyset)=0$,
 +
:(ii) $f$ is monotone, i.e. if $A\subseteq B\subseteq Q$ then $f(A)\le f(B)$,
 +
:(iii) $f$ is submodular, i.e. if $A$ and $B$ are different subsets of $Q$ then
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$$ \eqno{(2)}
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f(A)+f(B)\ge f(A\cap B) + f(A\cup B).
 +
$$
 +
</wikitex>

Версія за 15:12, 25 грудня 2009

[math]\operatorname{erfc}(x) = \frac{2}{\sqrt{\pi}} \int_x^{\infty} e^{-t^2}\,dt = \frac{e^{-x^2}}{x\sqrt{\pi}}\sum_{n=0}^\infty (-1)^n \frac{(2n)!}{n!(2x)^{2n}}[/math]

<wikitex> Let $Q$ be any finite set, and $\mathcal B=2^Q$ be the collection of the subsets of $Q$. Let $f:\mathcal B\rightarrow \mathbb R$ be a function assigning real numbers to the subsets of $Q$ and suppose $f$ satisfies the following conditions:

(i) $f(A)\ge 0$ for all $A\subseteq Q$, $f(\emptyset)=0$,
(ii) $f$ is monotone, i.e. if $A\subseteq B\subseteq Q$ then $f(A)\le f(B)$,
(iii) $f$ is submodular, i.e. if $A$ and $B$ are different subsets of $Q$ then

$$ \eqno{(2)}

f(A)+f(B)\ge f(A\cap B) + f(A\cup B).

$$ </wikitex>