Đặt $t=x^2-2x$, BPT trở thành:
$2^{t+1}+2^{-t+1}<5$
$\Leftrightarrow 2.2^{2t}-5.2^t+2<0$
$\Leftrightarrow \dfrac{1}{2}<2^t<2$
$\Leftrightarrow -1<t<1$
$\Leftrightarrow -1<x^2-2x<1$
$\Leftrightarrow \left\{\begin{array}{l}x\ne1\\1-\sqrt2<x<1+\sqrt2\end{array}\right.$