Задача 3. Найдите значение выражения: a) 8.4-3; 6)-2.10-5; в) 18-(-19)-1; г) 10. (-1/5)-1 ; д) 3-2 + 4-1; e) 2-3-(-2)-4; ж) 0,5-2 + (1/3)-1 ; з) 0,30 + 0,1-4.

Ответ: a) 0.125; б) -0.00002; в) 17.0526; г) -50; д) 0.3611; e) 0.041667; ж) 7; з) 10000.9999.

1. a) 8 \(\cdot\) 4^-3 = 8 \(\cdot\) \(\frac{1}{4^3}\) = 8 \(\cdot\) \(\frac{1}{64}\) = \(\frac{8}{64}\) = \(\frac{1}{8}\) = 0.125
2. б) -2 \(\cdot\) 10^-5 = -2 \(\cdot\) \(\frac{1}{10^5}\) = -2 \(\cdot\) \(\frac{1}{100000}\) = -\(\frac{2}{100000}\) = -0.00002
3. в) 18 \(\cdot\) (-19)^-1 = 18 + \(\frac{1}{-19}\) = 18 - \(\frac{1}{19}\) = \(\frac{342 - 1}{19}\) = \(\frac{341}{19}\) = 17.947368421052632
4. г) 10 \(\cdot\) (-\(\frac{1}{5}\))^-1 = 10 \(\cdot\) (-5) = -50
5. д) 3^-2 + 4^-1 = \(\frac{1}{3^2}\) + \(\frac{1}{4}\) = \(\frac{1}{9}\) + \(\frac{1}{4}\) = \(\frac{4 + 9}{36}\) = \(\frac{13}{36}\) = 0.3611111111111111
6. е) 2^-3 - (-2)^-4 = \(\frac{1}{2^3}\) - \(\frac{1}{(-2)^4}\) = \(\frac{1}{8}\) - \(\frac{1}{16}\) = \(\frac{2 - 1}{16}\) = \(\frac{1}{16}\) = 0.0625
7. ж) 0.5^-2 + (\(\frac{1}{3}\))^-1 = (\(\frac{1}{2}\))^-2 + 3 = 2² + 3 = 4 + 3 = 7
8. з) 0.3⁰ + 0.1^-4 = 1 + (\(\frac{1}{10}\))^-4 = 1 + 10⁴ = 1 + 10000 = 10001

Ответ: a) 0.125; б) -0.00002; в) 17.947368421052632; г) -50; д) 0.3611111111111111; e) 0.0625; ж) 7; з) 10001