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.
Expand 1/(1-x(1/4-x/10+x^2/40))
Expand 1/(1-x(1/4-x/10+x^2/40))
Natural Language
Math Input
Extended Keyboard
Examples
Upload
Random