Incorrect. Be sure to use the exponent rules: $\displaystyle{{\left({{x}}^{{n}}\right)}}^{{m}}={{x}}^{{{n}{m}}}\usepackage{cmbright}\Huge\$ and $\displaystyle{{x}}^{{n}}{{x}}^{{m}}={{x}}^{{{n}+{m}}}\usepackage{cmbright}\Huge\$ . In this case, $\displaystyle{{\left({{a}}^{{3}}{{a}}^{{-{{4}}}}\right)}}^{{2}}={{\left({{a}}^{{{3}-{4}}}\right)}}^{{2}}={{\left({{a}}^{{-{{1}}}}\right)}}^{{2}}\usepackage{cmbright}\Huge\$ . Does that help you solve this problem?