Đáp án:
\(\rm S=\left\{{1;\dfrac{4}{3}}\right\}\)
Giải thích các bước giải:
\(3x^2-7x+4=0\\\Leftrightarrow 3x^2 -3x - 4x + 4 = 0\\\Leftrightarrow 3x(x-1)-4(x-1)=0\\\Leftrightarrow(x-1)(3x-4)=0\\\Leftrightarrow\left[ \begin{array}{l}x-1=0\\3x-4=0\end{array} \right.\\\Leftrightarrow\left[ \begin{array}{l}x=1\\x=\dfrac{4}{3}\end{array} \right.\\\rm Vậy\,S=\left\{{1;\dfrac{4}{3}}\right\}\)
