Решебник по алгебре 8 класс Макарычев ФГОС Задание 311

 

\[\boxed{\text{311\ (311).}\text{\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]

\[\textbf{а)}\ \sqrt{x} = 4\]

\[x = 4^{2}\]

\[x = 16.\]

\[\textbf{б)}\ \sqrt{x} = 0,5\]

\[x = {0,5}^{2}\]

\[x = 0,25.\]

\[\textbf{в)}\ 2 \cdot \sqrt{x} = 0\]

\[\sqrt{x} = 0\]

\[x = 0.\]

\[\textbf{г)}\ 4 \cdot \sqrt{x} = 1\]

\[\sqrt{x} = \frac{1}{4}\]

\[x = \left( \frac{1}{4} \right)^{2}\]

\[x = \frac{1}{16}.\]

\[\textbf{д)}\ \sqrt{x} - 8 = 0\]

\[\sqrt{x} = 8\]

\[x = 8^{2}\]

\[x = 64.\]

\[\textbf{е)}\ 3 \cdot \sqrt{x} - 2 = 0\]

\[3\sqrt{x} = 2\]

\[\sqrt{x} = \frac{2}{3}\]

\[x = \left( \frac{2}{3} \right)^{2}\]

\[x = \frac{4}{9}.\]

\(\boxed{\text{311.}\text{\ }\text{еуроки}\text{-}\text{ответы}\text{\ }\text{на}\text{\ }\text{пятёрку}}\)

Пояснение.

Решение.

\[\textbf{а)}\ |a| = a;\ \ a > 0.\]

\[\textbf{б)}\ |c| = - c;\ \ \ c < 0.\]

\[\textbf{в)}\ \left| a^{2} \right| = a^{2}.\]

\[\textbf{г)}\ \left| a^{3} \right| = a^{3};\ \ a > 0.\]

\[\textbf{д)}\ \left| a^{3} \right| = - a^{3};\ \ a < 0.\]