Inverse mapping of the power function

b = JXG.JSXGraph.initBoard('jxgbox', {boundingbox: [-5.5, 7.5, 9.5, -2.5], axis: true});
b.suspendUpdate();

var n = b.create('slider',[[-5,-1],[5,-1],[-5,1,5]],{name:'n'});
b.create('functiongraph', [function(t){ return t}],{strokeColor:'#000000',dash:1,strokeWidth:1});
b.create('functiongraph', [function(t){ return JXG.Math.pow(t,n.Value()); },0.001,8],{strokeColor:'#ff0000'});
b.create('functiongraph', [function(t){ return JXG.Math.pow(t,1/n.Value()); },0.001,8],{strokeColor:'#ff0000',dash:2});
b.unsuspendUpdate();