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\$ . Also, remember that $\displaystyle{{a}}^{{n}}{{b}}^{{m}}={{b}}^{{m}}{{a}}^{{n}}\usepackage{cmbright}\Huge\$ . In this case, $\displaystyle{{\left({{a}}^{{-{{2}}}}{b}\right)}}^{{-{{2}}}}\cdot{{\left({{a}}^{{2}}{{b}}^{{3}}\right)}}^{{2}}\usepackage{cmbright}\Huge\$ can be simplified to $\displaystyle{{a}}^{{{\left(-{2}\right)}{\left(-{2}\right)}}}{{b}}^{{-{{2}}}}\cdot{{a}}^{{{2}{\left({2}\right)}}}{{b}}^{{{3}{\left({2}\right)}}}\usepackage{cmbright}\Huge\$ . Does this help you simplify the expression?