Школьник
Студент
Учитель
Личный кабинет
Назад
Вычисления
Банк ОГЭ
Скопировать ссылку
b37edcf8
Найдите значение выражения
7
⋅
21
⋅
3
\sqrt{7}\cdot \sqrt{21}\cdot \sqrt{3}
7
⋅
21
⋅
3
Ответ:
Ответить
Показать ответ
Ответ
Скрыть решение
Решение
Сообщить об ошибке
Решение
7
⋅
21
⋅
3
=
7
⋅
3
⋅
7
⋅
3
=
7
⋅
3
⋅
7
⋅
3
=
(
3
⋅
3
)
⋅
(
7
⋅
7
)
=
3
⋅
7
=
21
\begin{aligned}
{}& \sqrt{7}\cdot \sqrt{21}\cdot \sqrt{3} = \sqrt{7}\cdot \sqrt{3\cdot 7}\cdot \sqrt{3} = \\
& \sqrt{7}\cdot \sqrt{3}\cdot \sqrt{7}\cdot \sqrt{3} = \\
& (\sqrt{3}\cdot\sqrt{3})\cdot (\sqrt{7}\cdot\sqrt{7}) = \\
& 3\cdot 7 = 21
\end{aligned}
7
⋅
21
⋅
3
=
7
⋅
3
⋅
7
⋅
3
=
7
⋅
3
⋅
7
⋅
3
=
(
3
⋅
3
)
⋅
(
7
⋅
7
)
=
3
⋅
7
=
21
Ответ:
21
21
21
.
