[tex]log_6x=0,25=\frac{1}{4}\\\\log_6\frac{1}{\sqrt x}=log_6(\sqrt x)^{-1}=-log_6\sqrt x=-log_6x^{\frac{1}{2}}=-\frac{1}{2}log_6x=-\frac{1}{2}\cdot\frac{1}{4}=-\frac{1}{8}[/tex]