<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 ax²+bx+c=0.<br /><br /> <input type="text" maxlength="8" name="valA" value="8" size="4">x²+ <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>