2.339 Вычислите: а) (1\frac{1}{5})^2; б) (\frac{3}{4} - \frac{2}{3})^2; в) (\frac{1}{3})^3-(\frac{1}{9})^2.

Решение:

а) $$ (1\frac{1}{5})^2 = (\frac{6}{5})^2 = \frac{36}{25} = 1\frac{11}{25} $$

б) $$(\frac{3}{4} - \frac{2}{3})^2 = (\frac{9}{12} - \frac{8}{12})^2 = (\frac{1}{12})^2 = \frac{1}{144} $$

в) $$(\frac{1}{3})^3 - (\frac{1}{9})^2 = \frac{1}{27} - \frac{1}{81} = \frac{3}{81} - \frac{1}{81} = \frac{2}{81} $$

Ответ: а) $$1\frac{11}{25}$$; б) $$\frac{1}{144}$$; в) $$\frac{2}{81}$$