# Difference between revisions of "Inequalities"

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+ | To graph inequalities of the form | ||

+ | :<math> ay + bx + c <= 0 </math> | ||

+ | a line of the form | ||

+ | <source lang="javascript"> | ||

+ | line = b.create('line', [c, b, a]); | ||

+ | ineq = b.create('inequality', [line]), | ||

+ | </source> | ||

+ | and an equality of this line have to be created. | ||

+ | If one wants to show "greater than", ''inverse:true'' has to be used: | ||

+ | <source lang="javascript"> | ||

+ | line = b.create('line', [c, b, a]); | ||

+ | ineq = b.create('inequality', [line], {inverse:true}), | ||

+ | </source> | ||

+ | |||

+ | |||

<jsxgraph width="400" height="400" box="box1"> | <jsxgraph width="400" height="400" box="box1"> | ||

(function() { | (function() { |

## Revision as of 15:03, 16 December 2014

To graph inequalities of the form

- [math] ay + bx + c \lt= 0 [/math]

a line of the form

```
line = b.create('line', [c, b, a]);
ineq = b.create('inequality', [line]),
```

and an equality of this line have to be created.
If one wants to show "greater than", *inverse:true* has to be used:

```
line = b.create('line', [c, b, a]);
ineq = b.create('inequality', [line], {inverse:true}),
```

### The JavaScript code

```
var b = JXG.JSXGraph.initBoard('box1', {boundingbox: [-5, 5, 5, -5], axis:true});
var c = b.create('slider', [[-3,4], [2,4], [-5,1,5]]),
line1 = b.create('line', [function() { return [c.Value(), 0, -1]; }], {strokeColor: 'black'}),
ineq1 = b.create('inequality', [line1], {inverse: true}),
line2 = b.create('line', [1, 2, -3]), // Line y = 2/3 x + 1 or 0 = -3y + 2x +1
ineq2 = b.create('inequality', [line2], {fillColor: 'yellow'});
```