Question

Tìm số tự nhiên x sao cho: (5^x)² = 25¹¹

 

 

Answer 1

(5^x)²=25¹¹

\(\Rightarrow\)5^x.2=(5²)¹¹

^{\(\Rightarrow\)}5^2x=5²²

\(\Rightarrow\)2x=22

\(\Rightarrow\)x=22:2

\(\Rightarrow\)x=11

vậy x=11

Answer 2

\(\left(5^x\right)^2=25^{11}\)

Ta có :

\(\left(5^x\right)^2=\left(5^2\right)^{11}\)

`=>`\(5^{x\cdot2}=5^{2\cdot11}\)

\(\Rightarrow x\cdot2=2\cdot11=22\)

\(\Rightarrow x\cdot2=22\)

\(\Rightarrow x=22:2\)

\(\Rightarrow x=11\)

Vậy `x = 11`