\[\sqrt[3]{0,98} < \sqrt[4]{1,98};\ \ \]
\[так\ как\ \sqrt[3]{0,98} = \sqrt[12]{{0,98}^{4}};\ \ \]
\[\sqrt[4]{1,98} = \sqrt[12]{{1,98}^{3}};\]
\[{0,98}^{4} < {1,98}^{3}.\]