# Draggable exponential function

From JSXGraph Wiki

Revision as of 10:32, 16 February 2016 by A WASSERMANN (talk | contribs)

Plot the function
*y = e^{ax}*
where the parameter *a* is determined by the Point *A=(x_A, x_Y)*.

### The JavaScript code

```
var board = JXG.JSXGraph.initBoard('box1', {boundingbox: [-5, 20, 5, -1], axis:true});
var p = board.create('point', [1, Math.exp(1)]);
var graph = board.create('functiongraph', [
function(x) {
var a = Math.log(p.Y()) / p.X();
return Math.exp(a * x);
}]);
var txt = board.create('text', [-3, 10, function () {
return "a = " + (Math.log(p.Y()) / p.X()).toFixed(2);
}], {fontSize: 16});
```