// Define the ids of your boards in BOARDID0, BOARDID1,...
(function() {
const board1=JXG.JSXGraph.initBoard(BOARDID0,{boundingbox:[-3,3,3,-3], keepaspectratio:true});
var A = board1.create('point',[0,1]);
var B = board1.create('point',[1,1]);
var C = board1.create('point',[0,-1]);
var hyp = board1.create('hyperbola',[A,B,C]);
})();
(function() {
const board2=JXG.JSXGraph.initBoard(BOARDID1,{boundingbox:[-3,3,3,-3], keepaspectratio:true});
var A = board2.create('point',[-1,0]);
var B = board2.create('point',[1,0]);
var s = board2.create('slider',[[-1,-2],[1,-2],[0,0.5,3]]);
var hyp = board2.create('hyperbola',[A,B,function(){return s.Value();}]);
})();