Краткое пояснение: Складываем или вычитаем коэффициенты при одинаковых переменных.
- a) \(3m + 2m + 4m = (3 + 2 + 4)m = 9m\)
- б) \(\frac{1}{2}a + \frac{1}{3}a - \frac{1}{6}a = (\frac{1}{2} + \frac{1}{3} - \frac{1}{6})a = (\frac{3}{6} + \frac{2}{6} - \frac{1}{6})a = \frac{4}{6}a = \frac{2}{3}a\)
- в) \(0.9b - 1.3b + 0.7b = (0.9 - 1.3 + 0.7)b = 0.3b\)
- г) \(x - 0.2x - 0.7x = (1 - 0.2 - 0.7)x = 0.1x\)
- д) \(\frac{1}{12}m - \frac{1}{4}m - \frac{1}{3}m = (\frac{1}{12} - \frac{1}{4} - \frac{1}{3})m = (\frac{1}{12} - \frac{3}{12} - \frac{4}{12})m = -\frac{6}{12}m = -\frac{1}{2}m\)
- e) \(c - 0.8c - \frac{1}{5}c - \frac{1}{2}c = (1 - 0.8 - \frac{1}{5} - \frac{1}{2})c = (1 - 0.8 - 0.2 - 0.5)c = -0.5c\)
- ж) \(0.3a - 0.2b - 0.7a + 0.2b = (0.3 - 0.7)a + (-0.2 + 0.2)b = -0.4a + 0b = -0.4a\)
- з) \(4a - 6a - 2a + 12 - 11 = (4 - 6 - 2)a + (12 - 11) = -4a + 1\)
- и) \(\frac{2}{3}a + \frac{3}{8}b - \frac{1}{6}a - \frac{1}{4}b = (\frac{2}{3} - \frac{1}{6})a + (\frac{3}{8} - \frac{1}{4})b = (\frac{4}{6} - \frac{1}{6})a + (\frac{3}{8} - \frac{2}{8})b = \frac{3}{6}a + \frac{1}{8}b = \frac{1}{2}a + \frac{1}{8}b\)
- к) \(\frac{5}{7}k - \frac{2}{3} - \frac{3}{14}k - \frac{1}{3} = (\frac{5}{7} - \frac{3}{14})k + (-\frac{2}{3} - \frac{1}{3}) = (\frac{10}{14} - \frac{3}{14})k - \frac{3}{3} = \frac{7}{14}k - 1 = \frac{1}{2}k - 1\)
- л) \(0.2m - \frac{2}{9} - 4m + \frac{5}{9} = (0.2 - 4)m + (\frac{5}{9} - \frac{2}{9}) = -3.8m + \frac{3}{9} = -3.8m + \frac{1}{3}\)
- м) \(\frac{1}{2}a + \frac{1}{3}c - \frac{1}{2}a + \frac{2}{3}c = (\frac{1}{2} - \frac{1}{2})a + (\frac{1}{3} + \frac{2}{3})c = 0a + \frac{3}{3}c = 0 + 1c = c\)
Ответ: a) \(9m\); б) \(\frac{2}{3}a\); в) \(0.3b\); г) \(0.1x\); д) \(-\frac{1}{2}m\); e) \(-0.5c\); ж) \(-0.4a\); з) \(-4a + 1\); и) \(\frac{1}{2}a + \frac{1}{8}b\); к) \(\frac{1}{2}k - 1\); л) \(-3.8m + \frac{1}{3}\); м) \(c\)