You may have divided exponents to get the incorrect result of $\displaystyle{{w}}^{{2}}\cdot{{w}}^{{4}}\usepackage{cmbright}\Huge\$ , and then incorrectly simplified by multiplying the exponents. First use the quotient rule, $\displaystyle\frac{{{x}}^{{a}}}{{{x}}^{{b}}}={{x}}^{{{a}-{b}}}\usepackage{cmbright}\Huge\$ , to simplify each fraction. Then use the product rule, $\displaystyle{{x}}^{{a}}\cdot{{x}}^{{b}}={{x}}^{{{a}+{b}}}\usepackage{cmbright}\Huge\$ .