$1+\sqrt[3]{6}+\sqrt[3]{36}=1+\sqrt[3]{6}+{{(\sqrt[3]{6})}^{2}}=\frac{(1+\sqrt[3]{6}+{{(\sqrt[3]{6})}^{2}})(\sqrt[3]{6}-1)}{\sqrt[3]{6}-1}=\frac{{{(\sqrt[3]{6})}^{3}}-1}{\sqrt[3]{6}-1}=\frac{6-1}{\sqrt[3]{6}-1}=\frac{5}{\sqrt[3]{6}-1}$