Đáp án:
Giải thích các bước giải:
a) $|x-1|-13\cfrac{1}{2}=-5,5\\\Leftrightarrow |x-1|-\cfrac{27}{2}=-\cfrac{11}{2}\\\Leftrightarrow |x-1|=8\\TH1: x-1=8\\\Leftrightarrow x=9\\TH2: x-1=-8\\\Leftrightarrow x=-7$
Vậy S={-7; 9}
b) $\cfrac{(-2)^2}{|x|}=1\cfrac{3}{7}\\\Leftrightarrow \cfrac{4}{|x|}=\cfrac{10}{7}\\\Leftrightarrow |x|=\cfrac{14}{5}\\\Rightarrow x=\pm \cfrac{14}{5}$
Vậy $S=\{\cfrac{14}{5}; -\cfrac{14}{5}\}$
