Boundaries for double integrals?

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In summary, the relationship between x and y is defined as 0 < x < y < 1. This creates a loop where y is between x and 1, and x is between 0 and y. In a specific example, the answer can be found by evaluating the integral ∫∫8xy dx dy with bounds of 0 to y for the inner integral and 0 to 1 for the outer. To ensure the inequality is always satisfied, y is always kept less than x. A visual representation of this can be drawn by coloring the relevant area in a unit triangle, with the line y = x as a reference.
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sherrellbc
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And your boundaries are defined as: 0 < x < y < 1
How do you know the relationship between x and beyond this?

That is, we know that y is between x and 1, but x is between 0 and y. We have a loop. In a specific example, I know the answer is, where f(x,y) = 8xy

∫∫8xy dx dy

With bounds 0 to y, for the inner integral, and 0 to 1 for the outer.
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As an aside, I would make this much better, in terms of aesthetics, but I always have a very hard time with formatting for some reason.
 
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You let x run from 0 to 1, and for every value of x you let y run from x to 1. Then the inequality is always satisfied (if you make sure y < x then automatically x > y).

If unsure, draw a picture by coloring the relevant area in a unit triangle (hint: draw the line y = x).
 

FAQ: Boundaries for double integrals?

1. What are the bounds of a double integral?

The bounds of a double integral refer to the limits of integration for each variable in a two-dimensional region. These bounds can be expressed as a range of values or as functions of one or both variables.

2. How do you determine the bounds of a double integral?

The bounds of a double integral can be determined by visualizing the region of integration and identifying the range of values for each variable. This can also be done algebraically by setting up the double integral in terms of the variables and solving for the limits of integration.

3. Can the bounds of a double integral change?

Yes, the bounds of a double integral can change depending on the region of integration. They can also be transformed by changing the order of integration, which can make the integral easier to evaluate.

4. How do the bounds affect the value of a double integral?

The bounds of a double integral determine the area of the region being integrated over, which in turn affects the value of the integral. Different bounds can result in different values for the same integral.

5. What happens if the bounds of a double integral are incorrect?

If the bounds of a double integral are incorrect, the resulting value of the integral will also be incorrect. It is important to carefully determine the correct bounds in order to accurately evaluate the integral.

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