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.
limit as x -> 0 of (tan^2 x)/x^2 。（答：1。）
limit as x -> 0 of (tan^2 x)/x^2 。（答：1。）
Natural Language
Math Input
Extended Keyboard
