Ответ:

  1. а) Разложим знаменатели на множители: \(\frac{2a}{3(a+1)}+\frac{5a}{6(a+1)}=\frac{4a+5a}{6(a+1)}=\frac{3a}{2(a+1)}\).
  2. б) \(\frac{m}{4(m-1)}-\frac{m}{12(m-1)}=\frac{3m-m}{12(m-1)}=\frac{m}{6(m-1)}\).
  3. в) \(\frac{x}{2(x-y)}+\frac{3x}{8(x-y)}=\frac{4x+3x}{8(x-y)}=\frac{7x}{8(x-y)}\).
  4. г) \(\frac{4p}{9(p+q)}-\frac{p}{3(p+q)}=\frac{4p-3p}{9(p+q)}=\frac{p}{9(p+q)}\).
  5. д) \(\frac{x}{a(x+y)}+\frac{y}{b(x+y)}=\frac{bx+ay}{ab(x+y)}\).
  6. е) \(\frac{a}{c(b-d)}-\frac{c}{a(b-d)}=\frac{a^2-c^2}{ac(b-d)}=\frac{(a-c)(a+c)}{ac(b-d)}\).