我可以帮助您翻译。以下是翻译的结果,已保留HTML标签格式:
我尝试使用PHP制作一个二次方程求解器:
index.html:
<html>
<body>
<form action="findx.php" method="post">
Find solution for ax^2 + bx + c<br>
a: <input type="text" name="a"><br>
b: <input type="text" name="b"><br>
c: <input type="text" name="c"><br>
<input type="submit" value="Find x!">
</form>
</body>
</html>
findx.php:
<?php
if(isset($_POST['a'])){ $a = $_POST['a']; }
if(isset($_POST['b'])){ $b = $_POST['b']; }
if(isset($_POST['c'])){ $c = $_POST['c']; }
$d = $b*$b - 4*$a*$c;
echo $d;
if($d < 0) {
echo "The equation has no real solutions!";
} elseif($d = 0) {
echo "x = ";
echo (-$b / 2*$a);
} else {
echo "x1 = ";
echo ((-$b + sqrt($d)) / (2*$a));
echo "<br>";
echo "x2 = ";
echo ((-$b - sqrt($d)) / (2*$a));
}
?>
问题在于它返回错误的答案(d是正确的,x1和x2不是),似乎sqrt()返回了零或者其他什么东西。