fmpq.com
源代码：
点击运行
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>Fmpq教程(fmpq.com)</title> </head> <body> <p id="demo">单击按钮显示90度角的正切值。</p> <button onclick="myFunction()">点我</button> <script> function myFunction(){ document.getElementById("demo").innerHTML=Math.tan(90); } </script> </body> </html>
运行结果