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[(1-x)*y^n/(1-x^(n+1)),{n,0,Infinity}]
Sum[(1-x)*y^n/(1-x^(n+1)),{n,0,Infinity}]
Natural Language
Math Input
Extended Keyboard