Elliptic curves: Difference between revisions

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brd = JXG.JSXGraph.initBoard('jxgbox', {originX: 300, originY: 200, unitX: 20, unitY: 20, axis:true});
brd = JXG.JSXGraph.initBoard('jxgbox', {originX: 300, originY: 200, unitX: 20, unitY: 20, axis:true});
brd.suspendUpdate();
brd.suspendUpdate();
//
var b = brd.create('slider',[[1,-3],[10,-3],[-10,0,10]],{name:'a'});
var b = brd.createElement('slider',[[1,-3],[10,-3],[-10,0,10]],{name:'a'});
var a = brd.create('slider',[[1,-4],[10,-4],[-10,0,10]],{name:'b'});
var a = brd.createElement('slider',[[1,-4],[10,-4],[-10,0,10]],{name:'b'});
 
var c1 = brd.createElement('functiongraph', [function(x){ return Math.sqrt(x*x*x+a.Value()*x+b.Value()); }], {strokeWidth:3,strokeColor:'black'});
var c2 = brd.createElement('functiongraph', [function(x){ return -Math.sqrt(x*x*x+a.Value()*x+b.Value()); }], {strokeWidth:3,strokeColor:'black'});


var c1 = brd.create('functiongraph', [function(x){ return Math.sqrt(x*x*x+a.Value()*x+b.Value()); }],
                      {strokeWidth:3,strokeColor:'black'});
var c2 = brd.create('functiongraph', [function(x){ return -Math.sqrt(x*x*x+a.Value()*x+b.Value()); }],
                      {strokeWidth:3,strokeColor:'black'});
brd.unsuspendUpdate();
brd.unsuspendUpdate();
</script>  
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</source>
</source>
<source lang="javascript">
<source lang="javascript">
brd = JXG.JSXGraph.initBoard('jxgbox', {originX: 300, originY: 200, unitX: 20, unitY: 20});
JXG.Options.axis.strokeColor = '#cccccc';
brd = JXG.JSXGraph.initBoard('jxgbox', {originX: 300, originY: 200, unitX: 20, unitY: 20, axis:true});
brd.suspendUpdate();
brd.suspendUpdate();
brd.createElement('axis', [[0,0], [1,0]], {});
var b = brd.create('slider',[[1,-3],[10,-3],[-10,0,10]],{name:'a'});
brd.createElement('axis', [[0,0], [0,1]], {});
var a = brd.create('slider',[[1,-4],[10,-4],[-10,0,10]],{name:'b'});
//
var b = brd.createElement('slider',[[1,-3],[10,-3],[-10,1,10]],{name:'a'});
var a = brd.createElement('slider',[[1,-4],[10,-4],[-10,-8,10]],{name:'b'});
 
var c1 = brd.createElement('functiongraph', [function(x){ return Math.sqrt(x*x*x+a.Value()*x+b.Value()); }], {strokeWidth:3,strokeColor:'black'});
var c2 = brd.createElement('functiongraph', [function(x){ return -Math.sqrt(x*x*x+a.Value()*x+b.Value()); }], {strokeWidth:3,strokeColor:'black'});


var c1 = brd.create('functiongraph', [function(x){ return Math.sqrt(x*x*x+a.Value()*x+b.Value()); }],
                      {strokeWidth:3,strokeColor:'black'});
var c2 = brd.create('functiongraph', [function(x){ return -Math.sqrt(x*x*x+a.Value()*x+b.Value()); }],
                      {strokeWidth:3,strokeColor:'black'});
brd.unsuspendUpdate();
brd.unsuspendUpdate();
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Revision as of 07:22, 4 August 2010

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/jsxgraphcore.js"></script>
<div id="jxgbox" class="jxgbox" style="width:600px; height:400px;"></div>
JXG.Options.axis.strokeColor = '#cccccc';
brd = JXG.JSXGraph.initBoard('jxgbox', {originX: 300, originY: 200, unitX: 20, unitY: 20, axis:true});
brd.suspendUpdate();
var b = brd.create('slider',[[1,-3],[10,-3],[-10,0,10]],{name:'a'});
var a = brd.create('slider',[[1,-4],[10,-4],[-10,0,10]],{name:'b'});

var c1 = brd.create('functiongraph', [function(x){ return Math.sqrt(x*x*x+a.Value()*x+b.Value()); }],
                       {strokeWidth:3,strokeColor:'black'});
var c2 = brd.create('functiongraph', [function(x){ return -Math.sqrt(x*x*x+a.Value()*x+b.Value()); }], 
                       {strokeWidth:3,strokeColor:'black'});
brd.unsuspendUpdate();

References