Question

Trục căn thức ở mẫu của biểu thức  \(\frac{1}{1-\sqrt[3]{2}}\)

Answer 1

\(\frac{1}{1-\sqrt[3]{2}}=\frac{\left(1+\sqrt[3]{2}+\sqrt[3]{4}\right)}{\left(1-\sqrt[3]{2}\right)\left(1+\sqrt[3]{2}+\sqrt[3]{4}\right)}=\frac{1+\sqrt[3]{2}+\sqrt[3]{4}}{-1}\)

\(=-1-\sqrt[3]{2}-\sqrt[3]{4}\)

Answer 2

\(=\frac{\left(\sqrt[3]{2^2}+\sqrt[3]{2}+1\right)}{\left(1-\sqrt[3]{2}\right)\left(\left(\sqrt[3]{2^2}+\sqrt[3]{2}+1\right)\right)}\)

=\(\frac{\left(\sqrt[3]{2^2}+\sqrt[3]{2}+1\right)}{1-2}\)

\(-\left(\sqrt[3]{2^2}+\sqrt[3]{2}+1\right)\)