I have a question:
Let $A ∈ R^{m×n}$, and consider critical points of $f(v,w)=Av·w$, $v∈R^n, w∈R^m$
I need to find the gradient of $f(v,w)$ to solve it. I write $f(v,w)$ by double sum form but then I get stuck. $f(v,w)=\sum_{i=1}^m \sum_{j=1}^n a_{ij}v_jw_i$. To get $\nabla f$, how can I derive the partial derivative of $v$ if $f$ is written by components of $v$?