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.
sum(0,inf) of (1/4)(1/8)^n
sum(0,inf) of (1/4)(1/8)^n
Natural Language
Math Input
Extended Keyboard
