\(\Leftrightarrow\left\{{}\begin{matrix}m+1>0\\\Delta'=\left(m+1\right)^2-4\left(m+1\right)\ge0\end{matrix}\right.\)
\(\Leftrightarrow\left\{{}\begin{matrix}m>-1\\\left[{}\begin{matrix}m< -1\\m>3\end{matrix}\right.\end{matrix}\right.\) \(\Rightarrow m>3\)