Web references:
// Define the id of your board in BOARDID
const board = JXG.JSXGraph.initBoard(BOARDID, {
boundingbox: [-1.5, 2, 1.5, -1],
keepaspectratio: true
});
// Set visual attributes
var cerise = {
strokeColor: '#901B77',
fillColor: '#CA147A'
},
grass = {
strokeColor: '#009256',
fillColor: '#65B72E',
visible: true,
withLabel: true
},
perpendicular = {
strokeColor: 'black',
dash: 1,
strokeWidth: 1,
point: JXG.deepCopy(cerise, {
visible: true,
withLabel: true
})
},
median = {
strokeWidth: 1,
strokeColor: '#333333',
dash: 2
},
// Construct triangle ABC
A = board.create('point', [1, 0], cerise),
B = board.create('point', [-1, 0], cerise),
C = board.create('point', [0.2, 1.5], cerise),
pol = board.create('polygon', [A, B, C], {
fillColor: '#FFFF00',
lines: {
strokeWidth: 2,
strokeColor: '#009256'
}
});
// Orthocenter H
var pABC, pBCA, pCAB, i1;
perpendicular.point.name = 'H_c';
pABC = board.create('perpendicular', [pol.borders[0], C], perpendicular);
perpendicular.point.name = 'H_a';
pBCA = board.create('perpendicular', [pol.borders[1], A], perpendicular);
perpendicular.point.name = 'H_b';
pCAB = board.create('perpendicular', [pol.borders[2], B], perpendicular);
grass.name = 'H';
i1 = board.create('intersection', [pABC, pCAB, 0], grass);
// Centroid S
var mAB, mBC, mCA;
cerise.name = 'M_c';
mAB = board.create('midpoint', [A, B], cerise);
cerise.name = 'M_a';
mBC = board.create('midpoint', [B, C], cerise);
cerise.name = 'M_b';
mCA = board.create('midpoint', [C, A], cerise);
var ma, mb, mc, i2;
ma = board.create('segment', [mBC, A], median);
mb = board.create('segment', [mCA, B], median);
mc = board.create('segment', [mAB, C], median);
grass.name = 'S';
i2 = board.create('intersection', [ma, mc, 0], grass);
// Circumccenter U
grass.name = 'U';
var c = board.create('circumcircle', [A, B, C], {
strokeColor: '#000000',
dash: 3,
strokeWidth: 1,
center: grass
});
// Euler line: U, H and S are collinear
var euler = board.create('line', [i1, i2], {
strokeWidth: 2,
strokeColor: '#901B77'
});
This example is licensed under a Creative Commons Attribution 4.0 International License.
Please note that you have to mention The Center of Mobile Learning with Digital Technology in the credits.