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Übung: Definitions- und Wertebereich einer Funktion (grafisch)

1500 [ randRange( -9, -1 ), randRange( 1, 9 ) ] (function() { var functionPath = []; var prev; var push = function( val ) { prev = val; functionPath.push( prev ); }; push([ DOMAIN[0], randRange( -5, 5 ) ]); for( var i = DOMAIN[0]+1; i <= DOMAIN[1]; i++ ) { if ( abs( randRangeNonZero( -10, 10 ) < 2 ) && prev[1] < 8 ) { push([i, prev[1]+1]); } else if ( abs( randRangeNonZero( -10, 10 ) < 2 ) && prev[1] > -8 ) { push([i, prev[1]-1]); } else if ( abs( randRangeNonZero( -10, 10 ) < 2 ) && prev[1] < 7 ) { push([i, prev[1]+2]); } else if ( abs( randRangeNonZero( -10, 10 ) < 3 ) && prev[1] > -7 ) { push([i, prev[1]-2]); } else { push([i, prev[1]]); } } return functionPath; })() (function() { var values = $.map( FUNCTION_PATH, function( p ) { return p[1]; } ); return [ min.apply( null, values ), max.apply( null, values ) ]; })()

Die Funktion f(x) ist unten aufgetragen. Was ist ihr Definitionsbereich?

graphInit({ range: 10, scale: 20, axisArrows: "<->", tickStep: 1, labelStep: 1, unityLabels: false, labelFormat: function( s ) { return "\\small{" + s + "}"; } }); graph.fn_path = path( FUNCTION_PATH, { stroke: BLUE } ); circle( FUNCTION_PATH[0], 0.15, { stroke: "none", fill: BLUE } ); circle( FUNCTION_PATH[ FUNCTION_PATH.length - 1], 0.15, { stroke: "none", fill: BLUE } );

DOMAIN[0]  ≤ x ≤  DOMAIN[1]

Für welche Werte von x hat f(x) einen y-Wert?

Betrachten wir die x-Achse, als wäre sie ein Zahlenstrahl.

var domain_path = graph.fn_path.clone(); var tmp_path = path( $.map( FUNCTION_PATH, function( p ) { return [[ p[0], 0 ]]; }), { stroke: "none" } ); domain_path.animate( { path: tmp_path.attrs.path, "stroke-width": 4, stroke: GREEN }, ANIM_SPEED, "ease-in-out"); circle( [ FUNCTION_PATH[0][0], 0 ], 0.3, { stroke: "none", fill: GREEN, "fill-opacity": 0 } ) .animate( { "fill-opacity": 1.0 }, ANIM_SPEED, "ease-in-out" ); circle( [ FUNCTION_PATH[ FUNCTION_PATH.length - 1 ][0], 0 ], 0.3, { stroke: "none", fill: GREEN, "fill-opacity": 0 } ) .animate( { "fill-opacity": 1.0 }, ANIM_SPEED, "ease-in-out" ); tmp_path.remove();

\mathbb{D}_f = DOMAIN[0]\le x\le DOMAIN[1]

Die Funktion f(x) ist unten aufgetragen. Was ist ihr Wertebereich?

RANGE[0]  ≤ f(x) ≤  RANGE[1]

Für welche Werte ist f(x) definiert?

Betrachten wir die y-Achse, als wäre sie ein Zahlenstrahl.

var range_path = graph.fn_path.clone(); var tmp_path = path( $.map( FUNCTION_PATH, function( p ) { return [[ 0, p[1] ]]; }), { stroke: "none" } ); range_path.animate( { path: tmp_path.attrs.path, "stroke-width": 4, stroke: GREEN }, ANIM_SPEED, "ease-in-out"); circle( [ 0, RANGE[0] ], 0.3, { stroke: "none", fill: GREEN, "fill-opacity": 0 } ) .animate( { "fill-opacity": 1.0 }, ANIM_SPEED, "ease-in-out" ); circle( [ 0, RANGE[1] ], 0.3, { stroke: "none", fill: GREEN, "fill-opacity": 0 } ) .animate( { "fill-opacity": 1.0 }, ANIM_SPEED, "ease-in-out" ); tmp_path.remove();

\mathbb{W}_f = RANGE[0]\le f(x)\le RANGE[1]