████ ██████ ██ ██████

███ ██████

███ █████ – ████

████ ██████ ████ ██ ███ █████ ███████ ██ ███ ███ █████ ████████ ███████ ████. █████ ██████ █████ ████████, ███ █████ ██████ █████ ██████, ████ ██ █████ ███████ ███████ █████ ███ ███.

██ ██████ █████: ${\displaystyle \overrightarrow{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}=\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}$ ██ ███ ${\displaystyle \mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\overrightarrow{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}=\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}$.

██████ ██████ ██ ██████ ███: ”██ ███ █████ ████ ██████ ██ ██████ █████ ███ ███, ███ ██ ██ ████ █████ ███ ██ ██ ███ █████ ███████ ████.”

████ ██ █████ █████ █████ ██████ ████ ████ ████ ██████ - █████ █████ ██████████. ███ █████ ███████ ██████ ███ ███ ████ ████ ███████ ██ ████ █████. █████ ████ ██████ ███ █████ █████, ███ ██ ██████ ███████ ████ ██ ██████ █████. ███ ██ █████ ████ ██ █████ ███ █████ ████ ██ ███: ██████ ███████ ████ ██████ █████ ███████ ███████, █████ ██████ █████ ██ ████ █████.

██████ ██ ███████████

███████ ███ ██ ███████ ████ ██████ ██ ██████ ██████ ████ █████ ██████ ██████████ ███ █████ ██████ █████. ██████ ██████ ███████ █████ █████ ██████ ████████ ███████ █████ ██████ ██ █████ ██████, ████████ ██ ██████ ██████ ████ ██████ ███████ ██████ ██████████. ███████ █████ ██████ ███ ██████ ██████ █████ ██████ ██ ███████ ████ ██ ███████████.

███ ██████

████ ████ ████ ██████ ██ ███ ███ ████ ████████████ ████ █████ ████, ██████ ██████. ████ ██████████ ███ ████ ██ ████. ████ ████ ██ ████ ██████ ███████ ██:

${\displaystyle \mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}=\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}$ ${\displaystyle \mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}$ – ███, ${\displaystyle \mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}$ – ███, ${\displaystyle \mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}$ – █████.

██████: ████ ██ ██ █████ ████ █████ ███ ███████, █████ ██ ████ ████ ███ ██ █,███ ██████. ███ ████ ████, ██████ ████ ██████ ██ ██ ███ ██████ ██████. ██ ████ ████ █-█,███ ██████, ██████ ████ ██████ █-██ ███ ██████ ██████. █████ ███ ██ ██ █████ █████ ███ ███████, ███ ███ ██ █,███ ██████ █████ ██████ ██ ██ █ ███ ██████ ██████.

██ ████ ██ ███ ████ ████ ███, ██ ██ █████ █████ ██████ ████ ████ █████, ██████ ${\displaystyle \sum \overrightarrow{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}}$. █████ ███████ ████ █████ ██ ████ ████ ███████ ██:

${\displaystyle \sum \overrightarrow{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}=\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\overrightarrow{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}}$

█████, ██████ ███████ ████ ██ ███ █████ ██ ██ █████, ███ ███████ █████ ██████ ██ ████ ███ █████, ████ ███████ █████ ██ ██ ████ ██████ ███ ██████ █████, ███ ██ █████ ███████.

████ ████ ██ ████ ████ ██ ███████ ██ ███, █████ ████ ██ ████ ████████. ████ ████ ██ █████ █████ ████ ██ ███ █████ ██ ██████ ██ ██ ████ ████ ███ ██ ████ ███ ██ ███. ██████ ████ ${\displaystyle \overrightarrow{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}}$ █████ ██ ███ █████ ███ ███ ████:

${\displaystyle \sum \overrightarrow{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}=\frac{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\overrightarrow{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}}{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}}$

██████ ██████ ██ ██████ ███: "██████ ██████ ███ ████ ████████████ ███ ██████, ███████ ███ ████ █████ ████ █████". ██████ █████ ██ █████ "████ █████" █████ █████ █████ ███ █████ ██████.

██████ ██ █████ █████ "███", ███ █"████ ████" (████████ ██ ██████). ██████ ██████ ███████ ███ █████ █████, █████, ████ ████, ██ ██████ ██████ ███████ ████ ███ █████ ██ ██ ██████ ████ ████ ██ ██████. ██ ██ █████ ██ ███ ███ █████ ██ ███ ██████ ██ █████ ███ ███ █████ ██████ ████████ (█████, ███ █████ █████ ████ ████ ███ ██ ████ ███ ████ ██ ████ ██████).

██████ ████████ ███ ███████ "███" █"████". ███ ███ █████ ██████ ██ ███, ████ █████ ███ ████ ██████ █████ ████. ███ █████ ██ ███████ █████ ████ ███ ██████ ██ ███ ████ ████. ██ █████ ██ ████ ███ ████, ██ ████ █████ ██ ███████, █████ █████ ██ █████ █████████ █████ ████. ██ ██████ ████ ██████ ██ ████ ███ ████, █████ ████ █████.

█████ ██████ ████ █████ ████, ████ ██████ ██ ████ ██████ ██████████. ██████ ██████ ██ ████ ███ █████: "███ ████" ████ ████ ██ ████ ████, █"███ █████" ████ ████ ██ ███ ██████. ████ ███ ████ ████ █████ ██ ████ ████ ████ ███████.

███ ██████ ███████

███ ██ ██ ██████ ███████ ███████████ ███ █████. ████ ████ ██ ████ ███ █████ ███ █████ ██ ███ ███, ████ ████ █████ ███ █████ ███████ ██ █████ ███████ ██ ████ ██████.

██████ █████: ${\displaystyle {\overrightarrow{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}}_{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>},\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}=-{\overrightarrow{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}}_{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>},\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}}$.

██████ ███████ ██ ███ █████ █████ ████████ ███████ ██ ███ █████ █████, ███ ███ ██ ██████ ████ ██ ██ ██ ██ ██ ██ ██████ ████████ ███ ███.

█████ █████ ██ ███ ██████ ███ ██████ ████ ██████, ███████ █████ ██ ████ ██████ '███ ██████ ███████'. ██ ███, ███████ ████ ██████ ██████, ████ █████ ███ ████ ███ ████ ████, ████████ ████ ████ ███ ██████. █████ ███ ██████ ██████ ██-█████ ██████ ██ ████ ███ ███. ██████, ████ ████ █████ ███ █████ ██ ████. ██ ██ ████ ██████, ████ █████ ██ ████ ████ ███ █████ ██████ █████. ██ ████ ████ ███ ██ ████: ████ █████ ███ █████ ██ ████ ████, █████ ████ █████ ███ █████ ██████ █████. █████ ███ ██████ ██████ ██-█████ ██ ██ ███ ██████.

██ ██ █████ █████ ██ ████ ██████ ██ ██████, ████ ███ ███ ██████ ████ ██ ███ ████ █████ ██████, ██████ ██ ███ ████ ██ █████.

██-█████

███████ █████████████ ████ ████ ███ █████, ████ ██████ ██ ██████ ██ █████ ███. ████, ██████ ███ ███ █████ ██████ █████ █████ ████ █████ ██ ███, █████ ███ ███ ███ ██████ █████ ███ █████ ██ ████ █████ ████ ████ ██ █████ ███ ███ ██ ██████. ██ ███████ ███████ ████ ███ ███ ███ ███ ██████, ███ █████ █████ ██ ██████ ████ █████ ███ █████ ██ ████ ███ █████ ███ ██ ████ ████. ████ ███ ██, ███ ██████ ███████ █████ ███.

█████ ███ █████ ████

███ █████ ████ ███ ███ ████ ███████ █████ ███████ █████ ██ ████ █████ ██ ███, ████ ███ █████ ██████ ███ ████ ████████.

████ ██████ ███ ██ ████ ████ ██████ ██ ██████ █████ ███. ████ ██ ███ █████ █████ ███ █ █-█, ███████ ███████████ ██████. ████ ███ █ █████ ██ █ ███ ${\displaystyle \overrightarrow{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}}$. ██ ██ ████ ██████ ██ ██████, █ █████ █████ ██ ██ █ ███ ████ ██████, █████ ${\displaystyle -\overrightarrow{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}}$. ██ ██ ████ ████ ██ ██████ ████ ██████ ██ ███ ████ ████ ██████ ████ ███. ████ █████ ██ █ █████ ██ █ █████ █████ ██████ ████ ██ ████████ ███████. ██████ █████, ██ ████ ███ ███████ █-█ ████ █-█, █████. ███ ██ ██ ████ ████ ██ █ █-█ █████ ████.

███████████

███████████ █████ ████ ██████ ████, █████ ██████ ██████ ████. █████ ████ ███ ███████ ████ █████ ███████ ████ ██████ ██ ███ ████ ██████ ███. ██████ ███ ████, ███ ██████ ████████ ████████████, ████ █████ ████ ████ ███ █████ ██████ █████ ███████. ████ █████ ███ █████ ███ ███████ ████ ██ ██████ ████ ████ ██████ ███████ ████ ██████ █████ ███████ ███████, █████ ██████ █████ ██ ████ █████ ███ █████ █████ ██████ ██ ██████.

███ ██████ ██ ███ ████ ████

███ ██████ ██ ███ ████ ████ ███ █████ ██ ███ █████ ██ ████ ██ ██-████ █████ ████ ████ ███ ████ ███ ████, ██████ █████ ███ █████, ████ ██ ████ ██████ ██████ ███████. █████ ████ ████ ████ ██ ████ ████ █████ ██ █████ ███ ██ ████ ██ ███ █████ ███ ████ █████ ████ ██████ ████.

██████: ████ ████ ██████ █████ ${\displaystyle \mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}$ ███████ ${\displaystyle {\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}_{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}}$ ████████ ${\displaystyle \mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}$. ████ ████ █████ █████ ██████ ${\displaystyle \mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}$█████ ██████ (███ █████) ███ █████ ██ ███████ ███████ ${\displaystyle {\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}_{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}}$ ███████ ███ █████ ██ ████ ██████ ██ ██████. ████ ██████ █████ █████ ███ ███ ███ ████ ██████. ███ █████ ██ ████ ██████ █████ ██ ████ ██ █████ █████ ██████ ██████, █████ ████ ███:

${\displaystyle \mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\stackrel{\underset{}{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}}{=}\frac{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}=\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="3"\; class="word\; redacted">███</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}$. █████ ███████ ██████ █████ ███ ████ ██████ ██████ ███ ███ ${\displaystyle \mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}$ █████ ${\displaystyle \mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}_{}=\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}_{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}\mathrm{<span\; word-length="3"\; class="word\; redacted">███</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}$. █████ ████ ████ ██ █████ █████ █████ ██ ██████ ███ ███████, ${\displaystyle \mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}_{}=\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}_{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}\mathrm{<span\; word-length="3"\; class="word\; redacted">███</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}$ ████ █████ ██████ ██████ ████ ███: ${\displaystyle \mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\stackrel{\underset{}{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}}{=}\frac{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}=\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="3"\; class="word\; redacted">███</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}_{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}-(-\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="3"\; class="word\; redacted">███</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}_{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}})=\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="3"\; class="word\; redacted">███</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}({\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}_{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}+{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}_{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}})}$.

██████ ███ █████

██████ ███ █████ ███ ███ █████ ████, ██ ███ █████ ████ █████ █████, ██ ████ ██████ ██████, ████ ██ ██████ ██████ ████ ████ ██ ██████ █████ ████ ███████ █████ ████ ████████ ██ ████:

${\displaystyle \mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}=\frac{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}=\frac{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}(\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>})}$

███ ████ █████ ████ ████ ██████, ███ █████ █████ ███████ ████ ███ ██ ████ █████. ████ █████ ███ █████ ██ ████ ███████ ███████ ███ ████, ██ █████ ██ █████ █████ ███ ████ ████ ██ ██████ █████ ██ ██ █████ ████ ████ ███████ ███ █████ █████ ████. ██ ███ ██████ ████ ████ █████:

${\displaystyle \frac{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\overrightarrow{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}}{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}={\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}_{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}\frac{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\overrightarrow{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}}{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}+\overrightarrow{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}\frac{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}(\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}).}$ ██ ███████ ███ ██████ ██████, ███ ███ ████ ██████ ██████ ██████ ██ █████, ██ ███ █████ ██ █████ ███ ██████ █████ ███████████ █████ ███. ███ █████ █████ █████ ██ █████ █████ █████ █████ ██ ████ ███ ████ ██████/████████ ███ ██████ ████ ████ ██ ██████. █████ ██ █████ ██████ ███ █████ ██ ██████ ████:

${\displaystyle {\overrightarrow{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}}_{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}+\frac{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}\overrightarrow{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}={\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}_{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}\frac{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\overrightarrow{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}}{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}}$

████ ${\displaystyle \overrightarrow{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}}$ █████ ██ ██████ ████ ██████/███████ █████ ████ █████. ██████ ██ █████ █████ ███ █████ ████, ██ ████████ ██████ ██ ████ ██████ ███ ███ █████ ██ █████ ███, ██████ ███████ █-${\displaystyle \overrightarrow{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}=\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}\overrightarrow{\mathrm{<span\; word-length="1"\; class="word\; redacted">█</span>}}}$.