\left \{ {{log_3x=log_33^2} \atop {log_3x=log_33^{-2}}} \right. \ =>\left \{ {{x=9} \atop {x=\frac{1}{9}} } \right." alt="log_3^2x=4\\ \\ \left \{ {{log_3x=2} \atop {log_3x=-2}} \right. \ =>\left \{ {{log_3x=log_33^2} \atop {log_3x=log_33^{-2}}} \right. \ =>\left \{ {{x=9} \atop {x=\frac{1}{9}} } \right." align="absmiddle" class="latex-formula">