Giải thích các bước giải:
$(x^2-4)(x-1)(2x^2-7x+3)=0$
↔$(x-2)(x+2)(x-1)(2x-1)(x-3)=0$
↔$\left[\begin{array}{c}x-2=0\\x+2=0\\x-1=0\\2x-1=0\\x-3=0\end{array}\right.$
↔$\left[\begin{array}{c}x=2\\x=-2\\x=1\\x=\frac{1}{2}\\x=3\end{array}\right.$
=>$S=2+(-2)+1+\frac{1}{2}+3=\frac{9}{2}$
