Given $F(x,y,z) = (f(x,y,z),g(x,y,z),f(x,y,z) + g(x,y,z))$ I'm a little confused about what the derivative matrix would be.
Is it the 3 by 3 matrix $(DF_1, DF_2, DF_3)$ where $DF_1 = (\frac{\partial f}{\partial x} \;\; \frac{\partial f}{\partial y} \;\; \frac{\partial f}{\partial z})$ and similarly for $DF_2$ and $DF_3$ ?
Thanks.