2. Выполните действия: 1) \(\frac{16}{17}-\frac{15}{17}\); 2) \(\frac{8}{21}+\frac{3}{21}\); 3) \(\frac{5}{26}+(\frac{11}{26}-\frac{7}{26});\) 4) \((\frac{4}{11}+\frac{6}{11})-\frac{7}{11}\)

1) \(\frac{16}{17}-\frac{15}{17}=\frac{16-15}{17}=\frac{1}{17}\)

2) \(\frac{8}{21}+\frac{3}{21}=\frac{8+3}{21}=\frac{11}{21}\)

3) \(\frac{5}{26}+(\frac{11}{26}-\frac{7}{26})=\frac{5}{26}+\frac{11-7}{26}=\frac{5}{26}+\frac{4}{26}=\frac{5+4}{26}=\frac{9}{26}\)

4) \((\frac{4}{11}+\frac{6}{11})-\frac{7}{11}=\frac{4+6}{11}-\frac{7}{11}=\frac{10}{11}-\frac{7}{11}=\frac{10-7}{11}=\frac{3}{11}\)

Ответ: 1) \(\frac{1}{17}\); 2) \(\frac{11}{21}\); 3) \(\frac{9}{26}\); 4) \(\frac{3}{11}\)