\(\Leftrightarrow2^{2\left(x+3\right)}+16.2^{x+3}-17=0\)
Đặt \(2^{x+3}=t>0\)
\(\Rightarrow t^2+16t-17=0\Rightarrow\left[{}\begin{matrix}t=1\\t=-17< 0\left(l\right)\end{matrix}\right.\)
\(\Leftrightarrow2^{x+3}=1\)
\(\Leftrightarrow x+3=0\Leftrightarrow x=-3\)