Incorrect. Remember that the notation $\displaystyle{\left({f{-}}{g}\right)}{\left({x}\right)}\usepackage{cmbright}\Huge\$ means $\displaystyle{f{{\left({x}\right)}}}-{g{{\left({x}\right)}}}\usepackage{cmbright}\Huge\$ . Subtract the second polynomial from the first; distribute the minus sign and combine like terms. The procedure is the same for $\displaystyle{\left({g{-}}{f}\right)}{\left({x}\right)}\usepackage{cmbright}\Huge\$ , only in the reverse order.