Question

3^x+1=9^x

Answer 1

3^x+1=9^x

=>3^x+1=3^2x

=>x+1=2x

=>x=1

Answer 2

\(3^{x+1}=9^x\)

\(\Rightarrow3^{x+1}=\left(3^2\right)^x\)

\(\Rightarrow3^{x+1}=3^{2x}\)

\(\Rightarrow x+1=2x\)

\(\Rightarrow2x-x=1\)

\(\Rightarrow x=1\)

Answer 3

3^x+1=9^x

ma :9^x=(3²)^x

=> 3^x+1=(3²)^x

=> 3^x+1=3^2x

=>x+1=2x

2x chia hết cho x+1

ma 2x=(x+1).2-2

=>(x+1).2-2 CHIA HẾT CHO X+1

=>2 chia hết cho n+1

mà 2 chia hết cho 1;2

vậy x=0;1