- #1

- 41

- 2

[tex]

\frac{\partial f}{\partial x_i} = \frac{\partial f}{\partial \left( \sum_j {M^{-1}_{ij} y_j} \right)} = \sum_j Q_{ij} \frac{\partial f}{\partial y_j}

[/tex]

I suggest that the last identity is true for some matrix Q. Is there a general formula for Q?