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.
yabovip2019（网址:EDF6.COM）yabovip2019_yabovip2019_yabovip2019_ZZptZy93Z
Natural Language
Math Input
Extended Keyboard
Examples
Upload
Random
