A plot of function f(x)=tan(x) and f(x) =x

						var board = JXG.JSXGraph.initBoard('box1', {
boundingbox: [-5, 5, 5, -5],showcopyright: false,showNavigation: false,axis: true,defaultAxes: {
    y: { ticks: {majorHeight: 2 } },
	x: { ticks: {majorHeight: 2 } },
  }, 
});

board.create('functiongraph', [function(t){ return  Math.tan(t); },-Math.PI/2, Math.PI/2],{strokeColor: "blue",strokewidth:1});
var f1 = board.create('plot', ['(x)']);