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.
d^2/dx^2 f(x, y)+d^2/dy^2 f(x,y)=0
Natural Language
Math Input
Extended Keyboard
Examples
Upload
Random
