\(\Rightarrow\left[x\left(x+3\right)\right]\left[\left(x+1\right)\left(x+2\right)\right]+1=0\)
\(\Rightarrow\left[x^2+3x\right]\left[x^2+3x+2\right]+1=0\)
Đặt \(x^2+3x=k\)
\(\Rightarrow k\left(k+2\right)+1=0\)
\(\Rightarrow k^2+2k+1=0\)
\(\Rightarrow\left(k+1\right)^2=\left(x^2+3x+1\right)^2=0\)
Chịu