Question

(4x+2)(x²+1)=0

 

Answer 1

(4x + 2)(x² + 1) = 0

\(\Leftrightarrow\) \(\left[{}\begin{matrix}4x+2=0\\x^2+1=0\end{matrix}\right.\)\(\Leftrightarrow\) \(\left[{}\begin{matrix}x=\dfrac{-1}{2}\\x^2+1\left(2\right)\end{matrix}\right.\) 

(2) \(\Leftrightarrow\) x² + 1 = 0

\(\Leftrightarrow\) (x + 1)(x - 1) = 0

\(\Leftrightarrow\)\(\left[{}\begin{matrix}x+1=0\\x-1=0\end{matrix}\right.\) \(\Leftrightarrow\) \(\left[{}\begin{matrix}x=-1\\x=1\end{matrix}\right.\) 

S=\(\left\{\dfrac{-1}{2},1,-1\right\}\)