Question

so sanh 2^70 và 7^20

Answer 1

Ta có : 

\(2^{70}=\left(2^7\right)^{10}=128^{10}\)

\(7^{20}=\left(7^2\right)^{10}=49^{10}\)

Vì 128 > 49 nên \(128^{10}>49^{10}\)

Vậy \(2^{70}>7^{20}\) .

Answer 2

\(2^{70}=14^{10}\)

\(7^{20}=7^{10}.7^{10}\)

\(\Rightarrow2^{70}>7^{20}\)

Answer 3

\(2^{70}=2^{7.10}=\left(2^7\right)^{10}=128^{10}\)

\(7^{20}=7^{2.10}=\left(7^2\right)^{10}=49^{10}\)

\(128>49\Rightarrow128^{10}>49^{10}\Rightarrow2^{70}>7^{20}\)