I have this change of indices:
$$\sum_{j=0}^{\infty} \sum_{k=0}^{\infty} \frac{z^j}{j!} \frac{w^k}{k!} = \sum_{n=0}^{\infty} \sum_{k=0}^{n} \frac{z^{n-k}}{(n-k)!}$$\frac{w^k}{k!}
I'm not too sure how to get the k=0 to n inner indices.

Question

I have this change of indices: 
$$\sum_{j=0}^{\infty} \sum_{k=0}^{\infty} \frac{z^j}{j!} \frac{w^k}{k!} = \sum_{n=0}^{\infty} \sum_{k=0}^{n} \frac{z^{n-k}}{(n-k)!}$$\frac{w^k}{k!} 
I'm not too sure how to get the k=0 to n inner indices.

kirbykirby · Answer

Oops $$\sum_{j=0}^{\infty} \sum_{k=0}^{\infty} \frac{z^j}{j!} \frac{w^k}{k!} = \sum_{n=0}^{\infty} \sum_{k=0}^{n} \frac{z^{n-k}}{(n-k)!} \frac{w^k}{k!}$$

jigglypuff314 · Answer

Hello! This is the feedback group of this site, you would get better help if you posted this in the Mathematics group http://openstudy.com/study#/groups/Mathematics Good Luck! :)

xmoses1 · Answer

You could ask this in the $ \LaTeX~Practicing $ section. I bet someone there will know

xmoses1 · Answer

Oh wait never mind listen to @jigglypuff314 lol

kirbykirby · Answer

Oh I honestly don't know how I got to this part... I swear I was on the Math section :O

xmoses1 · Answer

XD it happens lol dont sweat it!