Question

Tìm x :

\(2^{n+3}+2^{n+2}+2^n=52\)

Answer 1

\(2^{n+3}+2^{n+2}+2^n=52\)

\(\Rightarrow2^n.2^3+2^n.2^2+2^n=52\)

\(\Rightarrow2^n.8+2^n.4+2^n.1=52\)

\(\Rightarrow2^n\left(8+4+1\right)=52\)

\(\Rightarrow2^n.13=52\)

\(\Rightarrow2^n=4\Leftrightarrow n=2\)

Answer 2

Đề bài là tìm n nha bn!

\(2^{n+3}+2^{n+2}+2^n=52\\ 2^n\left(2^3+2^2+1\right)=52\\ 2^n\left(8+4+1\right)=52\\ 2^n.13=52\\ 2^n=52:13\\ 2^n=4\\ 2^n=\pm2^2\\ \Rightarrow n=2\)