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.
pc2.8（网址:EDF6.COM）pc2.8_pc2.8_pc2.8_pc2.8_pc2.8pc2.8_pc2.8_pc2.8_gsIBVgh4h
Natural Language
Math Input
Extended Keyboard
Examples
Upload
Random
