Uh oh! Wolfram|Alpha doesn't run without JavaScript.
Please enable JavaScript. If you don't know how, you can find instructions
here
.
Once you've done that, refresh this page to start using Wolfram|Alpha.
lim_{x->0+}sum_{k=1}^infty k^3 exp(-kx*(1+sqrt(2)))cos(kx)
Natural Language
Math Input
Extended Keyboard
Examples
Upload
Random