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.
abs((x-1 ) mod 4)-2)-1, plot from % 20-4% 20to% 204
Natural Language
Math Input
Extended Keyboard
Examples
Upload
Random