\(2022x^2+2022x+4022=0\)
\(\Leftrightarrow x^2+x+\dfrac{2011}{1011}=0\)
\(\Leftrightarrow x^2+2.\dfrac{1}{2}x+\dfrac{1}{4}+\dfrac{7033}{4044}=0\)
\(\Leftrightarrow\left(x+\dfrac{1}{2}\right)^2+\dfrac{7033}{4044}=0\) (vô nghiệm vì \(\left(x+\dfrac{1}{2}\right)^2+\dfrac{7033}{4044}\ge\dfrac{7033}{4044}\forall x\))
-Vậy S=∅