Efectuati:
6. a) \frac{x+5}{6} - \frac{2x-2}{3}
b) \frac{x-1}{2} + \frac{3x-1}{4} - \frac{5x-1}{6}
c) \frac{2a+3b}{2} - \frac{a-2b}{3} + \frac{a-b}{4} - \frac{23b}{12}
7. a) \frac{1}{x-1} - \frac{2x}{1- x^{2} } + \frac{1}{x+1}

Multumesc anticipat! :)