Incorrect. Be sure you are excluding values for b that will make the numerator or the denominator of the divisor equal to 0. Then rewrite the expression as multiplication by the reciprocal and multiply normally: $\displaystyle\frac{{{b}-{2}}}{{{{b}}^{{2}}-{4}}}\cdot\frac{{{{b}}^{{2}}-{4}}}{{{b}}}\usepackage{cmbright}\Huge\$ . Make sure to factor $\displaystyle{\left({{b}}^{{2}}-{4}\right)}\usepackage{cmbright}\Huge\$ before pulling it out of the expression; this will help you figure out which values for b are excluded from the domain.