Đặt \(\left\{{}\begin{matrix}x-1=a\\x+3=b\end{matrix}\right.\) \(\Rightarrow a+b=2x+2\)
PT đã cho có dạng là :
\(a^3+b^3=\left(a+b\right)^3\)
\(\Leftrightarrow3ab\left(a+b\right)=0\)
\(\Leftrightarrow3\left(x-1\right)\left(x+3\right)\left(2x+2\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x=1\\x=-3\\x=-1\end{matrix}\right.\) ( thỏa mãn )