- #1

Icebreaker

## Main Question or Discussion Point

Please let me know if I derived this correctly (I did it a while back, and can't find the notebook):

[tex]v(x,y)=u(r(x,y),s(x,y))[/tex]

(derivations)

At some point I come across this:

[tex]\frac{\partial}{\partial x} \frac{\partial u}{\partial r}[/tex]

which I wrote as

[tex]\frac{\partial^2 u}{\partial r^2} \frac{\partial r}{\partial x}[/tex]

Is it right?

[tex]v(x,y)=u(r(x,y),s(x,y))[/tex]

(derivations)

At some point I come across this:

[tex]\frac{\partial}{\partial x} \frac{\partial u}{\partial r}[/tex]

which I wrote as

[tex]\frac{\partial^2 u}{\partial r^2} \frac{\partial r}{\partial x}[/tex]

Is it right?