<Text-field layout="Heading 1" style="Heading 1"><Font family="Times New Roman">Type I Regions</Font></Text-field>

Maple can evaluate double integrals!!

Here's what it looks like:

with(student):

f := (x,y) -> 1-x-y;

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a := 0; b := 1;

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g1 := x -> 0; g2 := x -> 1-x;

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Doubleint(f(x,y), y=g1(x)..g2(x), x=a..b);

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Now let's use value to evaluate it....

value(Doubleint(f(x,y), y=g1(x)..g2(x), x=a..b));

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f := (x,y) -> 1/200*exp(-x/20)*exp(-y/10);

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a := 0; b := 30;

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g1 := x -> 0; g2 := x -> 30-x;

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Doubleint(f(x,y), y=g1(x)..g2(x), x=a..b);

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Now let's use value to evaluate it....

value(Doubleint(f(x,y), y=g1(x)..g2(x), x=a..b));

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evalf(%);

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