3. Solve the equation $2^{1-2|x|}+2 \cdot 4^{1+|x|}=17$.
Solution:

$$
2^{2|x|}=t \geq 1, \quad 8 t^{2}-17 t+2=0, \quad t=2, \quad 2^{2|x|}=2, \quad 2|x|=1, \quad x= \pm \frac{1}{2} \quad \text{Answer}: x= \pm \frac{1}{2}
$$