437 Вправа 437Алгебра 8 клас Бевз 2025 · § 9 · стор. 89

437. Обчисли.

а) ${\displaystyle 9^{-1}=}$${\displaystyle \frac{1}{9}}$;

б) ${\displaystyle 7^{-2}=}$${\displaystyle \frac{1}{7^2}=}$${\displaystyle \frac{1}{49}}$;

в) ${\displaystyle {(-3)}^{-3}=}$${\displaystyle \frac{1}{{(-3)}^3}=}$${\displaystyle -\frac{1}{27}}$;

г) ${\displaystyle {\left(\frac{1}{13}\right)}^{-1}=}$${\displaystyle 13}$;

ґ) ${\displaystyle {\left(1\frac{1}{3}\right)}^{-2}=}$${\displaystyle {\left(\frac{4}{3}\right)}^{-2}=}$${\displaystyle {\left(\frac{3}{4}\right)}^2=}$${\displaystyle \frac{9}{16}}$.