a) TA CÓ: \(5^{217}>5^{216}=\left(5^3\right)^{72}=125^{72}>119^{72}\Rightarrow5^{217}>119^{72}\)
b) Ta có: \(37^{1320}=\left(37^2\right)^{660}=1369^{660}\); \(11^{1979}< 11^{1980}=\left(11^3\right)^{660}=1331^{660}\)Mà
\(1369^{660}>1331^{660}\Rightarrow37^{1320}>11^{1970}\)