2. Сократите дроби: 1) 3x+3y/6c 2) 4m-4n/8a 3) 2a+2b/4a-4b 4) 12a-3/6a+9 5) ac-bc/ac+bc 6) a-ab/a 7) a^2/a^2+ab 8) pq^3/p^2q-pq^2 9) 7a+14b/3a+6b 10) 2m^2-mn/2mn-n^2 11) 3b-6a/12b-6a 12) x^2-2xy/2y^2-xy

Решение:

1. \( \frac{3x+3y}{6c} = \frac{3(x+y)}{6c} = \frac{x+y}{2c} \)
2. \( \frac{4m-4n}{8a} = \frac{4(m-n)}{8a} = \frac{m-n}{2a} \)
3. \( \frac{2a+2b}{4a-4b} = \frac{2(a+b)}{4(a-b)} = \frac{a+b}{2(a-b)} \)
4. \( \frac{12a-3}{6a+9} = \frac{3(4a-1)}{3(2a+3)} = \frac{4a-1}{2a+3} \)
5. \( \frac{ac-bc}{ac+bc} = \frac{c(a-b)}{c(a+b)} = \frac{a-b}{a+b} \)
6. \( \frac{a-ab}{a} = \frac{a(1-b)}{a} = 1-b \)
7. \( \frac{a^2}{a^2+ab} = \frac{a^2}{a(a+b)} = \frac{a}{a+b} \)
8. \( \frac{pq^3}{p^2q-pq^2} = \frac{pq^3}{pq(p-q)} = \frac{q^2}{p-q} \)
9. \( \frac{7a+14b}{3a+6b} = \frac{7(a+2b)}{3(a+2b)} = \frac{7}{3} \)
10. \( \frac{2m^2-mn}{2mn-n^2} = \frac{m(2m-n)}{n(2m-n)} = \frac{m}{n} \)
11. \( \frac{3b-6a}{12b-6a} = \frac{3(b-2a)}{6(2b-a)} \) (не сокращается)
12. \( \frac{x^2-2xy}{2y^2-xy} = \frac{x(x-2y)}{y(2y-x)} \) (не сокращается)

Ответ: \( \frac{x+y}{2c} \), \( \frac{m-n}{2a} \), \( \frac{a+b}{2(a-b)} \), \( \frac{4a-1}{2a+3} \), \( \frac{a-b}{a+b} \), \( 1-b \), \( \frac{a}{a+b} \), \( \frac{q^2}{p-q} \), \( \frac{7}{3} \), \( \frac{m}{n} \), \( \frac{3(b-2a)}{6(2b-a)} \), \( \frac{x(x-2y)}{y(2y-x)} \).