在线一元二次方程式计算器 源码

上次做数学题,解方程解的难受,于是乎,在参考别人源码的过程中,写出了自己的计算器

  1 <html>
  2 <head>
  3 <meta http-equiv="Content-Type" content="text/html" charset="utf-8">
  4 <title>在线一元二次方程式计算器</title>
  5 </head>
  6 <body>
  7 <form name="fquad">
  8     <p align="center">解二次方程式计算<br>
  9      </p>
 10     <table align="center">
 11         <tbody>
 12             <tr>
 13                 <td bgcolor="#990000">
 14                 <h2><font color="#ffffff"><input size="4" name="fa" type="text"> x<sup>2</sup>+ <input size="4" name="fb" type="text"> x + <input size="4" name="fc" type="text"> = 0 <input onclick="checkQuad()" type="button" value="解题"> <input type="reset" value="重置"> </font></h2>
 15                 <p align="center"><font color="#ffffff" face="Arial"><b>一元二次方程的解法</b></font></p>
 16                 </td>
 17             </tr>
 18             <tr>
 19                 <td bgcolor="#990000">
 20                 <h2><font color="#ffffff">x<sub><a style="text-decoration: none" ><font color="#ffffff">1</font></a></sub>=<input size="45" name="x1" type="text"> <br>
 21                 x<sub>2</sub>=<input size="45" name="x2" type="text"> </font></h2>
 22                 </td>
 23             </tr>
 24             <tr>
 25                
 26             </tr>
 27         </tbody>
 28     </table>
 29 </form>
 30 <p align="center">Made by CRoot</p>
 31 <script language="JavaScript">
 32 <!-- 
 33 var rootparti;
 34 var rootpart;
 35 var det;
 36 var rootparti1;
 37 var rootparti2;
 38 var a;
 39 var b;
 40 var c;
 41 var x1;
 42 var x2;
 43 var i = "i";
 44 function checkQuad() {
 45 var a = document.fquad.fa.value;
 46 var b = document.fquad.fb.value;
 47 var c = document.fquad.fc.value;
 48 if (a == 0 && c != 0) {
 49 x1 = -c / b;
 50 x2 = "Not a quadratic equation, but here is your answer for x";
 51 document.fquad.x1.value=x1;
 52 document.fquad.x2.value=x2;
 53 }
 54 else if (a == "" && c != 0) {
 55 x1 = -c / b;
 56 x2 = "Not a quadratic equation";
 57 document.fquad.x1.value=x1;
 58 document.fquad.x2.value=x2;
 59 }
 60 else {
 61 quad();
 62    }
 63 }
 64 function quad() {
 65 var a = document.fquad.fa.value;
 66 var b = document.fquad.fb.value;
 67 var c = document.fquad.fc.value;
 68 det = Math.pow(b,2) - 4 * a * c;
 69 rootpart = Math.sqrt(det) / (2 * a);
 70 rootparti = (Math.sqrt(-det) / (2 * a)) + i;
 71 if (parseFloat(rootparti) < 0) {
 72 rootparti1 = rootparti;
 73 rootparti2 = (-1 * parseFloat(rootparti)) + i;
 74 }
 75 else {
 76 rootparti1 = (-1 * parseFloat(rootparti)) + i;
 77 rootparti2 = rootparti;
 78 }
 79 if (rootparti1 == "1i") {
 80 rootparti1 = i;
 81 rootparti2 = "-i";
 82 }
 83 else if (rootparti1 == "-1i") {
 84 rootparti1 = "-i";
 85 rootparti2 = i;
 86 }
 87 if (det == 0) {
 88 x1 = x2 = -b / (2 * a);
 89 }
 90 else if (det > 0) {
 91 x1 = (-b + Math.sqrt(det)) / (2 * a);
 92 x2 = (-b - Math.sqrt(det)) / (2 * a);
 93 }
 94 else if ((-b / (2 * a)) == 0) {
 95 x1 = rootparti1;
 96 x2 = rootparti2;
 97 }
 98 else {
 99 x1 = (-b / (2 * a) + " + " + rootparti1);
100 x2 = (-b / (2 * a) + " + " + rootparti2);
101 }
102 document.fquad.x1.value=x1;
103 document.fquad.x2.value=x2;
104 }
105 // will solve for complex numbers
106 
107 //   -->
108 </script>
109 </body>
110 </html>

解二次方程式计算

x2+ x + = 0

一元二次方程的解法

x1=
x2=

Made by CRoot

原文地址:https://www.cnblogs.com/croot/p/3235106.html