Iterative integration is a technical integration.

Integral in principle is just a principle. Whether it can be integrated or not, it usually becomes repeated integration.

Only in special cases, double integrals do not need to be converted into repeated integrals, for example, in electrostatics.

If it is applied to the special symmetry of Gauss theorem, it can be achieved in one step, which is a special case.

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The specific process is:

1, first draw according to the integral area;

2. Then consider how to arrange the order, and the integration process will become simple.

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Please refer to the following picture examples, each picture can be clicked to enlarge;

If you have any questions, please ask them. If you have any questions, you will have answers.

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Sincere request

Please have the right to choose and certify professional answers.

Never certify that my answer to this question is "professional answer".

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Once certified as a "professional answer", all netizens can't comment, discuss and supervise.

If the answer is wrong, you won't get fair criticism from netizens, which is unfair and unfair.

Correcting your mistakes, improving your ability to answer questions and answering questions objectively have many disadvantages.

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I really need to get all kinds of feedback on my answers. Please don't be certified as a professional answer.

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Please understand, please do not authenticate. Thank you for understanding! Thank you for understanding! Thank you. Thank you.

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