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.
立即下载APP（永久链接:SE8.TV）立即下载APP_立即下载APP_立即下载APP_aLa2ah1ha
Natural Language
Math Input
Extended Keyboard
Examples
Upload
Random
