Question

tìm x 

3^2x-1=243

Answer 1

3^2x-1=243

Mà 243=3⁵

=>2x-1=5

=>2x=5+1

=>2x=6

=>x=6:2

=>x=3

Answer 2

\(3^{2x-1}=243=3^5\)

\(\Rightarrow2x-1=5\)

\(\Rightarrow2x=6\)

\(\Rightarrow x=3\)

Answer 3

\(3^{2x-1}=243\)

\(3^{2x-1}=3^5\)

\(\Rightarrow2x-1=5\)

\(2x=6\)

\(x=3\)

Answer 4

Ta có: \(3^{2x-1}=243=>3^{2x-1}=3^3=>2x-1=3=>2x=4\)

=> x=2

Vậy...