Question

Bài 1 :Tìm x

\(3^{2x}.9^x=9^2.27\)

Answer 1

\(\Rightarrow3^{2x}\cdot3^{2x}=3^4\cdot3^3\\ \Rightarrow3^{4x}=3^7\\ \Rightarrow4x=7\Rightarrow x=\dfrac{7}{4}\)

Answer 2

\(3^{2x}.9^x=9^2.27\Rightarrow3^{2x}.3^{2x}=3^4.3^3\Rightarrow3^{4x}=3^7\Rightarrow4x=7\Rightarrow x=\dfrac{7}{4}\)

Answer 3

\(3^{2x}\cdot9^x=9^2\cdot27\)

\(\Leftrightarrow3^{4x}=3^4\cdot3^3=3^7\)

\(\Leftrightarrow x=\dfrac{7}{4}\)