Let $f : \mathbb{R}^{N \times 1} \to \mathbb{R}$ be a
D4364: Real function such that
| (i) |
\begin{equation}
\exists \, A \in \mathbb{R}^{N \times N} :
\forall \, x \in \mathbb{R}^{N \times 1} :
f(x) = x^T A x
\end{equation}
|
| (ii) |
\begin{equation}
A^T
= A
\end{equation}
|
Let $L : \mathbb{R}^{N \times 1} \to \mathbb{R}$ be a
D4364: Real function such that
| (i) |
$x_0 \in \mathbb{R}^{N \times 1}$ is a D5200: Real column matrix
|
| (ii) |
\begin{equation}
\forall \, x \in \mathbb{R}^{N \times 1} :
L(x) = 2 (A x_0 )^T x
\end{equation}
|
