2. a) 1/16 - 3/16; б) 6/3 - (-1/2); в) 5/18 - 1/24.

a) \(\frac{1}{16} - \frac{3}{16} = \frac{1-3}{16} = \frac{-2}{16} = -\frac{1}{8}\) б) \(\frac{6}{3} - \left(-\frac{1}{2}\right) = \frac{6}{3} + \frac{1}{2} = 2 + \frac{1}{2} = \frac{4}{2} + \frac{1}{2} = \frac{5}{2}\) в) \(\frac{5}{18} - \frac{1}{24} = \frac{5\cdot4}{18\cdot4} - \frac{1\cdot3}{24\cdot3} = \frac{20}{72} - \frac{3}{72} = \frac{17}{72}\)