This technique requires an understanding and recognition of complex numbers.

Specifically Euler's formula:

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Recognize, for example, that the real portion:

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Given an integral of the general form:

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We can complexify it:

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With basic rules of exponents:

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*It can be proven that the "real portion" operator can be moved outside the integral:*

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The integral easily evaluates:

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Multiplying and dividing by (1-2i):

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Which can be rewritten as:

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Applying Euler's forumula:

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Expanding:

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Taking the Real part of this expression:

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So:

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