Question

3^x+1 + 3^x+2 = 108

Answer 1

\(3^{x+1}+3^{x+2}=108\\ \Leftrightarrow3^{x+1}\left(1+3\right)=108\\ \Leftrightarrow3^{x+1}\cdot4=108\\ \Leftrightarrow3^{x+1}=27=3^3\\ \Rightarrow x+1=3\\ \Leftrightarrow x=2\)

Answer 2

\(\Leftrightarrow3^x\cdot3+3^x\cdot9=108\)

\(\Leftrightarrow3^x\cdot12=108\)

\(\Leftrightarrow3^x=9\)

hay x=2

Answer 3

x=2