Б. Сложение и вычитание дробей с разными знаменателями
Задание 6. Выполните действие:
- \( \frac{x+2}{3} + \frac{x+2}{3} = \frac{x+2+x+2}{3} = \frac{2x+4}{3} \)
- \( \frac{x+2}{3} + \frac{x-2}{3} = \frac{x+2+x-2}{3} = \frac{2x}{3} \)
- \( \frac{2a-3}{4} + \frac{3a-3}{4} = \frac{2a-3+3a-3}{4} = \frac{5a-6}{4} \)
- \( \frac{2a-3}{4} - \frac{4}{4} = \frac{2a-3-4}{4} = \frac{2a-7}{4} \)
- \( \frac{5b-a}{2} - \frac{2}{2} = \frac{5b-a-2}{2} \)
- \( \frac{5b-a}{2} - \frac{5b-a}{2} = \frac{(5b-a)-(5b-a)}{2} = 0 \)
- \( \frac{3-2x}{a} - \frac{3-2x}{a} = \frac{(3-2x)-(3-2x)}{a} = 0 \)
- \( \frac{m}{8} - \frac{y-b}{8} = \frac{m-(y-b)}{8} = \frac{m-y+b}{8} \)
- \( \frac{x^2-y^2}{a} - \frac{2x^2}{a} = \frac{x^2-y^2-2x^2}{a} = \frac{-x^2-y^2}{a} \)
- \( \frac{2a+3b-5}{a^2} + \frac{5b-2a}{a^2} = \frac{2a+3b-5+5b-2a}{a^2} = \frac{8b-5}{a^2} \)
- \( \frac{2a+3b-5}{a^2} - \frac{5b-2a}{a^2} = \frac{2a+3b-5-(5b-2a)}{a^2} = \frac{2a+3b-5-5b+2a}{a^2} = \frac{4a-2b-5}{a^2} \)
- \( \frac{8-x^2+2x}{3a} + \frac{3x^2-8-x^2}{3a} = \frac{8-x^2+2x+3x^2-8-x^2}{3a} = \frac{x^2+2x}{3a} \)
- \( \frac{8-x^2+2x}{3a} - \frac{3x^2}{3a} = \frac{8-x^2+2x-3x^2}{3a} = \frac{8-4x^2+2x}{3a} \)
- \( \frac{15+x+y+7b}{4ab} \)
- \( \frac{14m-n}{xy} - \frac{2n-3m}{xy} = \frac{14m-n-(2n-3m)}{xy} = \frac{14m-n-2n+3m}{xy} = \frac{17m-3n}{xy} \)
- \( \frac{3a^3+x}{4a} - \frac{5x-2a^3}{4a} = \frac{3a^3+x-(5x-2a^3)}{4a} = \frac{3a^3+x-5x+2a^3}{4a} = \frac{5a^3-4x}{4a} \)