Question

so sánh

\(9^8\:.\:5^{16\:}\)và \(19^{20}\)

Answer 1

9⁸.5¹⁶=9⁸.(5²)⁸=(9.25)⁸=225⁸

19²⁰=(19²)¹⁰=361¹⁰>361⁸>225⁸

=>19²⁰>9⁸.5¹⁶

Answer 2

Ta có :

\(9^8.5^{16}=9^8.\left(5^2\right)^8=9^8.25^8=\left(9.25\right)^8=225^8\)

\(19^{20}=\left(19^2\right)^{10}=361^{10}\)

Vì : \(361^{10}>361^8>225^8\)

\(\Rightarrow361^{10}>225^8\) hay \(19^{20}>9^8.5^{16}\)

Vậy \(19^{20}>9^8.5^{16}\)