<span>Найдите значение выражения.
1) Упростим выражение:
![\frac{ a^{2} - b^{2} }{ab} : (\frac{1}{b} - \frac{1}{a} ) = \frac{(a-b)(a+b)}{ab} : (\frac{1*a}{ab} - \frac{1*b}{ab})](https://tex.z-dn.net/?f=+%5Cfrac%7B+a%5E%7B2%7D+-++b%5E%7B2%7D+%7D%7Bab%7D+%3A++%28%5Cfrac%7B1%7D%7Bb%7D++-++%5Cfrac%7B1%7D%7Ba%7D+%29+%3D++%5Cfrac%7B%28a-b%29%28a%2Bb%29%7D%7Bab%7D+%3A++%28%5Cfrac%7B1%2Aa%7D%7Bab%7D+-++%5Cfrac%7B1%2Ab%7D%7Bab%7D%29+)
=
![\frac{(a-b)(a+b)}{ab} : \frac{a-b}{ab} = \frac{(a-b)(a+b)}{ab} * \frac{ab}{a-b} = a+b](https://tex.z-dn.net/?f=+%5Cfrac%7B%28a-b%29%28a%2Bb%29%7D%7Bab%7D+%3A++%5Cfrac%7Ba-b%7D%7Bab%7D+%3D++%5Cfrac%7B%28a-b%29%28a%2Bb%29%7D%7Bab%7D+%2A++%5Cfrac%7Bab%7D%7Ba-b%7D+%3D+a%2Bb)
2) Подставим числовые значения:
а=
![7\frac{2}{17}](https://tex.z-dn.net/?f=+7%5Cfrac%7B2%7D%7B17%7D+)
b=
![6\frac{15}{17}](https://tex.z-dn.net/?f=+6%5Cfrac%7B15%7D%7B17%7D+)
a+b = </span>
![7\frac{2}{17}](https://tex.z-dn.net/?f=+7%5Cfrac%7B2%7D%7B17%7D+)
+
![6\frac{15}{17}](https://tex.z-dn.net/?f=+6%5Cfrac%7B15%7D%7B17%7D+)
= (7+6) +
![\frac{2+15}{17}](https://tex.z-dn.net/?f=+%5Cfrac%7B2%2B15%7D%7B17%7D+)
= 13 <span>
![7\frac{17}{17}](https://tex.z-dn.net/?f=+7%5Cfrac%7B17%7D%7B17%7D+)
= 14
Ответ: 14</span>
<span>ctg (3 arctg( -sqrt 3 /3)-2 arctg(sqrt(-3)))</span>
Ln 1 = 0
эта натуральный лагарифм - основание e
e^0=1