Предмет: Алгебра, автор: rightforvard17

помогите найти значение выражения

Приложения:

Ответы

Автор ответа: wangross

2

$\sqrt{9-4 \sqrt{5} } - \sqrt{5} = \sqrt{(2- \sqrt{5})^2 } - \sqrt{5} =|2-\sqrt{5} |-\sqrt{5} = \\ =-2+\sqrt{5} -\sqrt{5} =-2$

Мы раскрыли модуль со сменой знака, потому что под модулем стоит отрицательное выражение.

Ответ: $-2$

rightforvard17: а куда убирается 9?

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