Elliptic curves: Difference between revisions

From JSXGraph Wiki
No edit summary
No edit summary
Line 13: Line 13:
//
//
var b = brd.createElement('slider',[[1,-3],[10,-3],[-10,1,10]],{name:'a'});
var b = brd.createElement('slider',[[1,-3],[10,-3],[-10,1,10]],{name:'a'});
brd.createElement('text',[12,-3,'a']);
brd.createElement('text',[12,-3,'(a)']);
var a = brd.createElement('slider',[[1,-4],[10,-4],[-10,1,10]],{name:'b'});
var a = brd.createElement('slider',[[1,-4],[10,-4],[-10,1,10]],{name:'b'});
brd.createElement('text',[12,-4,'b']);
brd.createElement('text',[12,-4,'(b)']);


var c1 = brd.createElement('curve', [function(x){ return x; }, function(x){ return Math.sqrt(x*x*x+a.Value()*x+b.Value()); }, 'x'], {strokeWidth:3,strokeColor:'black'});
var c1 = brd.createElement('curve', [function(x){ return x; }, function(x){ return Math.sqrt(x*x*x+a.Value()*x+b.Value()); }, 'x'], {strokeWidth:3,strokeColor:'black'});
Line 21: Line 21:




var g1 = brd.createElement('glider',[3,1,c1],{name:'S'});
var g1 = brd.createElement('glider',[3,3,c1],{name:'S'});


brd.unsuspendUpdate();
brd.unsuspendUpdate();

Revision as of 18:17, 30 January 2009

An elliptic curve can be written as a plane algebraic curve defined by an equation of the form

[math]\displaystyle{ y^2=x^3+ax+b\,. }[/math]

<link rel="stylesheet" type="text/css" href="http://jsxgraph.uni-bayreuth.de/distrib/jsxgraph.css" />
<script type="text/javascript" src="http://jsxgraph.uni-bayreuth.de/distrib/prototype.js"></script>
<script type="text/javascript" src="http://jsxgraph.uni-bayreuth.de/distrib/jsxgraphcore.js"></script>
<div id="jxgbox" class="jxgbox" style="width:600px; height:400px;"></div>