Ответ:

  1. \(\frac{3(x+y)}{6c}=\frac{x+y}{2c}\).
  2. \(\frac{8a}{4(m-n)}=\frac{2a}{m-n}\).
  3. \(\frac{2(a+b)}{4(a-b)}=\frac{a+b}{2(a-b)}\).
  4. \(\frac{3(4a-1)}{3(2a+3)}=\frac{4a-1}{2a+3}\).
  5. \(\frac{c(a-b)}{c(a+b)}=\frac{a-b}{a+b}\).
  6. \(\frac{a(1+b)}{a(1-b)}=\frac{1+b}{1-b}\).

Ответ: 1) \(\frac{x+y}{2c}\); 2) \(\frac{2a}{m-n}\); 3) \(\frac{a+b}{2(a-b)}\); 4) \(\frac{4a-1}{2a+3}\); 5) \(\frac{a-b}{a+b}\); 6) \(\frac{1+b}{1-b}\).