Вариант ІІ 1. Вычислите: 5 1. a) +=; 7 デナデ 3 6)+; 56' 1 81 8 8' e) 92' ; 52 2. Вычислите: 1 + a) 16 ( 7 B) 15 (ж 3 1 +; 3' 3 5 ; 4 16 1 2 г) 2015 3)72 22 33 3 1 + 6) 1 1 5 3 16 4 + + 12 18 18 12 ; B) 23 +23 5 4 20

Ответ: смотри решение ниже

1. Вариант II.
1. Вычислите:
1. \[\frac{5}{7} + \frac{1}{7} = \frac{5+1}{7} = \frac{6}{7}\]
2. \[\frac{3}{5} + \frac{1}{6} = \frac{3 \cdot 6}{5 \cdot 6} + \frac{1 \cdot 5}{6 \cdot 5} = \frac{18}{30} + \frac{5}{30} = \frac{18+5}{30} = \frac{23}{30}\]
3. \[\frac{7}{15} + \frac{1}{3} = \frac{7}{15} + \frac{1 \cdot 5}{3 \cdot 5} = \frac{7}{15} + \frac{5}{15} = \frac{7+5}{15} = \frac{12}{15} = \frac{4}{5}\]
4. \[\frac{1}{20} + \frac{2}{15} = \frac{1 \cdot 3}{20 \cdot 3} + \frac{2 \cdot 4}{15 \cdot 4} = \frac{3}{60} + \frac{8}{60} = \frac{3+8}{60} = \frac{11}{60}\]
5. \[\frac{5}{8} - \frac{2}{8} = \frac{5-2}{8} = \frac{3}{8}\]
6. \[\frac{8}{9} - \frac{1}{2} = \frac{8 \cdot 2}{9 \cdot 2} - \frac{1 \cdot 9}{2 \cdot 9} = \frac{16}{18} - \frac{9}{18} = \frac{16-9}{18} = \frac{7}{18}\]
7. \[\frac{3}{4} - \frac{5}{16} = \frac{3 \cdot 4}{4 \cdot 4} - \frac{5}{16} = \frac{12}{16} - \frac{5}{16} = \frac{12-5}{16} = \frac{7}{16}\]
8. \[\frac{7}{22} - \frac{2}{33} = \frac{7 \cdot 3}{22 \cdot 3} - \frac{2 \cdot 2}{33 \cdot 2} = \frac{21}{66} - \frac{4}{66} = \frac{21-4}{66} = \frac{17}{66}\]
2. Вычислите:
1. \[\frac{1}{16} + (\frac{3}{16} + \frac{1}{4}) = \frac{1}{16} + (\frac{3}{16} + \frac{1 \cdot 4}{4 \cdot 4}) = \frac{1}{16} + (\frac{3}{16} + \frac{4}{16}) = \frac{1}{16} + \frac{7}{16} = \frac{1+7}{16} = \frac{8}{16} = \frac{1}{2}\]
2. \[\frac{1}{12} + \frac{1}{18} + \frac{5}{18} + \frac{3}{12} = (\frac{1}{12} + \frac{3}{12}) + (\frac{1}{18} + \frac{5}{18}) = \frac{4}{12} + \frac{6}{18} = \frac{1}{3} + \frac{1}{3} = \frac{1+1}{3} = \frac{2}{3}\]
3. \[\frac{2}{5} + \frac{3}{4} - \frac{23}{20} = \frac{2 \cdot 4}{5 \cdot 4} + \frac{3 \cdot 5}{4 \cdot 5} - \frac{23}{20} = \frac{8}{20} + \frac{15}{20} - \frac{23}{20} = \frac{8+15-23}{20} = \frac{0}{20} = 0\]

Ответ: смотри решение выше