Giải phương trình: (1-1/3+(x/(1-1/3)/(1+1/3-1/1-1/3)=8/7

$\frac{1-\frac{1}{3}+\frac{x}{1-\frac{1}{3}}}{1+\frac{1}{3}-\frac{1}{1-\frac{1}{3}}}=\frac{8}{7}\iff \frac{\frac{2}{3}+\frac{x}{\frac{2}{3}}}{\frac{4}{3}-\frac{1}{\frac{2}{3}}}=\frac{8}{7}$

$\iff \frac{4+9x}{6}:\left(-\frac{1}{6}\right)=\frac{8}{7}\iff \frac{4+9x}{6}=\frac{-4}{21}$

$\iff 84+189x=-24\iff 189x=-108\iff x=-\frac{4}{7}$