initial

CwJ/integrals/riemann.js

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+const b = JXG.JSXGraph.initBoard('jsxgraph', {
+    boundingbox: [-0.5,0.3,1.5,-1/4], axis:true
+});
+
+var g = function(x) { return x*x*x*x +  10*x*x - 60* x + 100}
+var f = function(x) {return 1/Math.sqrt(g(x))};
+
+var type = "right";
+var l = 0;
+var r = 1;
+var rsum = function() {
+    return JXG.Math.Numerics.riemannsum(f,n.Value(), type, l, r);
+};
+var n =   b.create('slider', [[0.1, -0.05],[0.75,-0.05], [2,1,50]],{name:'n',snapWidth:1});
+
+
+
+
+var graph = b.create('functiongraph', [f, l, r]);
+var os = b.create('riemannsum',
+                  [f,
+                   function(){ return n.Value();},
+                   type, l, r
+                  ],
+                  {fillColor:'#ffff00', fillOpacity:0.3});
+
+
+
+b.create('text', [0.1,0.25, function(){
+    return 'Riemann sum='+(rsum().toFixed(4));
+}]);