Quadratic Formula Calculator

QuatraticForumalCalc.html

<SCRIPT language="JavaScript">
<!--

//Quadratic Calculator, by Taydron
//http://www.taydron-domain.net
//Visit JavaScript Kit (http://javascriptkit.com) for script

function quadData1() {
var valA = document.quadCalc.valA.value;
var valB = document.quadCalc.valB.value;
var valC = document.quadCalc.valC.value;
var disc = (valB*valB)-(4*valA*valC);
var r_disc = Math.sqrt(disc);
var vax1 = (-valB+r_disc)/(2*valA);
var vax2 = (-valB-r_disc)/(2*valA);
var ing1 = ((valA*vax1*vax1*vax1)/3)+((valB*vax1*vax1)/2)+(valC*vax1);
var ing2 = ((valA*vax2*vax2*vax2)/3)+((valB*vax2*vax2)/2)+(valC*vax2);
var inte = ing1-ing2;
var sec_dx = (-valB)/(2*valA);
var sec_dy = (valA*sec_dx*sec_dx)+(valB*sec_dx)+(1*valC);
var e_val;
vax1 = Math.round(vax1*100)/100;
vax2 = Math.round(vax2*100)/100;
inte = Math.round(inte*100)/100;
sec_dx = Math.round(sec_dx*100)/100;
sec_dy = Math.round(sec_dy*100)/100;
if (valA == 0) {document.quadCalc.answer1.value = "This curve is not a quadratic. Enter a non-zero value in the first box.";} 
 else {
 if (disc>0) {
  document.quadCalc.answer1.value = "The curve intercepts the x-axis at: " +vax1+ " and " +vax2+ ".";
   {
   if (inte>0) {document.quadCalc.answer2.value = inte;} 
   if (inte<0) {document.quadCalc.answer2.value = -inte;} 
   if (inte=0) {document.quadCalc.answer2.value = 0;}
   }
  } if (disc<0) {
  document.quadCalc.answer1.value = "The curve has no real roots, because it does not intercept the real x-axis.";
  document.quadCalc.answer2.value = "N/A";
  } if (disc=0) {
  document.quadCalc.answer1.value = "The curve touches the x-axis at: " +vax1+ ".";
  document.quadCalc.answer2.value = "N/A";
  }
 document.quadCalc.answer3.value = (2*valA)+ "x+" +valB;
 if (valA<0) {e_val = "maximum";} 
 if (valA>0) {e_val = "minimum";} 
 document.quadCalc.answer4.value = e_val;
 document.quadCalc.answer5.value = sec_dx+ " , " +sec_dy;
  }
 }
//-->
</SCRIPT>

<b>Quadratic Calculator</b>
<form name="quadCalc">

A quadratic is a curve of the parabola family.<br />
They are written in the format ax<sup>2</sup>+bx+c=0.<br /><br />
<input type="text" maxlength="8" name="valA" value="8" size="4">x<sup>2</sup>+
<input type="text" maxlength="8" name="valB" value="10" size="4">x+
<input type="text" maxlength="8" name="valC" value="2" size="4">=0<br />
<input type="button" onClick=quadData1() value="Calculate"> <input type="reset" value="Reset"><br />
<input type="text" name="answer1" readonly="readonly" size="60"><br />
The area bounded by the curve above the x-axis is: <input type="text" name="answer2" readonly="readonly" size="6"> sq. units.<br />
The gradient of the curve at any point is: <input type="text" name="answer3" size="10">.<br />
The <input type="text" name="answer4" readonly="readonly" size="8"> value of the curve occurs at co-ordinates: <input type="text" name="answer5" readonly="readonly" size="10">.
</form>

<p align="center">This free script provided by<br />
<a href="http://www.javascriptkit.com">JavaScript
Kit</a></p>