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.
Graph of -Exp[-r]/r + 0.25/(2*r^2) from 0 to 2
Natural Language
Math Input
Extended Keyboard
Examples
Upload
Random