a) \(\left(-3+\frac{3}{x}-\frac{1}{3}\right)\div\left(1+\frac{2}{5}+\frac{2}{3}=-\frac{5}{4}\right)\)
b) \(-\frac{3x}{4}\times\left(\frac{1}{x}+\frac{2}{7}\right)=0\)
c) \(3-\frac{1-\frac{1}{2}}{1+\frac{1}{x}}=2\frac{2}{3}\)
Help me!!! Cần gấp trong 10 phút.