Question

Tìm x, biết:

|-2|.3^x+3^x+2=99

Answer 1

\(\left|-2\right|\cdot3^x+3^{x+2}=99\)

\(\Rightarrow2\cdot3^x+3^x\cdot3^2=99\)

\(\Rightarrow3^x\cdot\left(2+3^2\right)=99\)

\(\Rightarrow3^x\cdot11=99\)

\(\Rightarrow3^x=99:11\)

\(\Rightarrow3^x=9\)

\(\Rightarrow3^x=3^2\)

\(\Rightarrow x=2\)