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Gebietsintegral übersetzen
int2-03-01
radio
56
randRange(1,8) randRangeExclude(1,8,[X])

Gegeben sei das Dreieck \color{orange}D.



graphInit({ range: [[-2, 9],[-9, 9]], scale: [20,20], tickStep: [1,1], gridStep: [1,1], labelStep: [2,2], gridOpacity: 0.1, axisOpacity: 0.8, tickOpacity: 0.6, labelOpacity: 0.8 }); label( [ 0, 9.5 ], "y", "above" ); label( [9.5,0 ], "x", "right" ); line( [0, -Y], [0, Y], { stroke: ORANGE } ); line( [0,-Y], [X, 0], { stroke: ORANGE } ); line( [X,0], [0, Y], { stroke: ORANGE } )

Dann ist \displaystyle \int \int_{{\color{orange}D}} f(x,y) \, dA = \ldots?

\displaystyle \int_{0}^{X} \int_{fractionReduce(Y,X,small=true) x - Y}^{-fractionReduce(Y,X,small=true) x +Y} f(x,y) \, dy dx

Es ist (z.B.) {\orange{D}} \subset \mathbb R^2 gegeben durch {\orange{D}} = \left\{ (x,y) \, | \, 0 \leq x \leq X, \; fractionReduce(Y,X) x - Y \leq y \leq -fractionReduce(Y,X) x +Y\right\}.

Damit schreibt sich dann \displaystyle \int\int_{\orange{D}} f(x,y) dA = \int_{0}^{X} \int_{fractionReduce(Y,X,small=true) x - Y}^{-fractionReduce(Y,X,small=true) x +Y} f(x,y) \, dy dx