حاصل عبارت ${{x}^{۷}}-x\left( {{x}^{۶}}+{{x}^{۵}}+{{x}^{۴}}-{{x}^{۵}}-{{x}^{۴}}-{{x}^{۳}} \right)$ برابر است با:
${{x}^{7}}-x\left( {{x}^{6}}+{{x}^{5}}+{{x}^{4}}-{{x}^{5}}-{{x}^{4}}-{{x}^{3}} \right)={{x}^{7}}-{{x}^{7}}-{{x}^{6}}-{{x}^{5}}+{{x}^{6}}+{{x}^{5}}+{{x}^{4}}={{x}^{4}}$