Question

Answer 1

\(\Leftrightarrow3^x\left(1+3^2\right)=270\)

\(\Leftrightarrow3^x=27\)

hay x=3

Answer 2

Ta có: \(3^x+3^{x+2}=270\)

\(\Rightarrow3^x+3^x.9=270\)

\(\Rightarrow3^x\left(1+9\right)=270\)

\(\Rightarrow3^x=27\Rightarrow x=3\)

Answer 3

\(\Rightarrow3^X+3^X.3^2=270\)

\(\Rightarrow3^X.\left(3^2+1\right)=270\)

\(\Rightarrow3^X.10=270\)

\(\Rightarrow3^X=27\)

\(\Rightarrow3^X=3^3\)

\(\Rightarrow x=3\)