Problem with the region of an integral

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In summary, the conversation discusses calculating the circulation of a vector field on the border of a set called Omega. The person understands the solution but is confused about the region, which is delimited by two intersecting functions. The upper function does not stop at y=3, as it is given by y=3+sqrt(9-x^2). The region includes all y-values for x>=0 and ranges from 0 to 6 for x=0 and 0 to 3 for x=3.
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Amaelle
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Homework Statement
look at the image
Relevant Equations
Stocke theorem!
Greetings!

The exercice ask to calculate the circuitation of the the vector field F on the border of the set omega
I do understand the solution very well
my problem is the region!
I m used to work with a region delimitated clearly by two intersecting function here the upper one stop a y=3 and doesn´t intersect with y=0.

thank you!
1644355492888.png
 
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Amaelle said:
I m used to work with a region delimitated clearly by two intersecting function here the upper one stop a y=3 and doesn´t intersect with y=0.
No, the upper function doesn't stop at y = 3. The quarter circle does, but the function is given by ##y = 3 + \sqrt{9 - x^2}##.
The region ##\Omega## is (obviously) the portion in blue. The inequality ##0 \le y \le 3 + \sqrt{9 - x^2}## includes all those y-values for which ##x \ge 0##, that run from the x-axis up to the quarter circle. For example, if x = 0, y ranges from 0 to 6; if x = 3, y ranges from 0 to 3.
 
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  • #3
Mark44 said:
No, the upper function doesn't stop at y = 3. The quarter circle does, but the function is given by ##y = 3 + \sqrt{9 - x^2}##.
The region ##\Omega## is (obviously) the portion in blue. The inequality ##0 \le y \le 3 + \sqrt{9 - x^2}## includes all those y-values for which ##x \ge 0##, that run from the x-axis up to the quarter circle. For example, if x = 0, y ranges from 0 to 6; if x = 3, y ranges from 0 to 3.
Thanks a million!
 

FAQ: Problem with the region of an integral

What is the region of an integral?

The region of an integral refers to the area or volume bounded by the curve(s) and the x-axis or y-axis. It is the region over which the integral is being evaluated.

What are some common problems with the region of an integral?

Some common problems with the region of an integral include determining the correct limits of integration, identifying the correct type of integral (single or double), and dealing with non-standard or irregularly shaped regions.

How do you determine the limits of integration for a given region?

The limits of integration can be determined by finding the points of intersection between the curves that bound the region and the x-axis or y-axis. These points become the upper and lower limits of integration, depending on the direction of integration.

What is the difference between a single and a double integral?

A single integral is used to find the area under a curve, while a double integral is used to find the volume between a surface and the x-y plane. A double integral involves integrating over two variables (x and y) instead of just one.

How do you handle non-standard or irregularly shaped regions in an integral?

In these cases, the region can be divided into smaller, simpler shapes such as rectangles, triangles, or semicircles. The integral can then be evaluated separately for each shape and the results can be added together to find the total area or volume of the region.

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