0\\2x<1\\ x<\frac{1}{2}\\ \log_3 (1-2x)<\log_33^{-1}\\ 1-2x<\frac{1}{3}\\ 2x>1-\frac{1}{3}\\ 2x>\frac{2}{3}\\ x>\frac{1}{3}\\\\ x\in(\frac{1}{3},\frac{1}{2}) " alt="\\\log_3 (1-2x)<-1\\ 1-2x>0\\2x<1\\ x<\frac{1}{2}\\ \log_3 (1-2x)<\log_33^{-1}\\ 1-2x<\frac{1}{3}\\ 2x>1-\frac{1}{3}\\ 2x>\frac{2}{3}\\ x>\frac{1}{3}\\\\ x\in(\frac{1}{3},\frac{1}{2}) " align="absmiddle" class="latex-formula">