You multiplied $\displaystyle{x}{\left({2}{{x}}^{{2}}+{3}{x}+{1}\right)}\usepackage{cmbright}\Huge\$ , not $\displaystyle{{x}}^{{2}}{\left({2}{{x}}^{{2}}+{3}{x}+{1}\right)}\usepackage{cmbright}\Huge\$ .