Giải thích các bước giải:
a/ (2x-4).(x-3)=0
⇔ 2(x-2)(x-3)=0
⇔ \(\left[ \begin{array}{l}x-2=0\\x-3=0\end{array} \right.\)
⇔ \(\left[ \begin{array}{l}x=2\\x=3\end{array} \right.\)
Vậy S={2;3}
b/ $2^{x}$+2²=2².3
⇔ $2^{x}$=2².3-2²
⇔ $2^{x}$=8
⇔ $2^{x}$=2³
⇔ x=3
Vậy S={3}
c/ $2^{x}$+$2^{x}$+1=12
⇔ 2.$2^{x}$=11
⇔ $2^{x}$=$\frac{11}{2}$
⇔ x=$\frac{log(11/2)}{log(2)}$