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 ((x-c)^2+y^2)((x+c)^2+y^2
expand ((x-c)^2+y^2)((x+c)^2+y^2
Natural Language
Math Input
Extended Keyboard