Short improper integral question (how to rewrite?)

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The discussion centers on rewriting an improper integral using substitution. A participant suggests substituting x with -x, which raises concerns about the legality of the operation. Another clarifies that this is a valid approach through u-substitution, specifically u = -x, and emphasizes the importance of adjusting the integration boundaries accordingly. The original poster confirms understanding after this explanation. The thread concludes with the poster expressing gratitude for the assistance.
vantz
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Homework Statement


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Homework Equations


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The Attempt at a Solution


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I'm trying to rewrite the integral as shown

Most probably a real simple answer

Thank you
 
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In the first integral, try substituting x for -x.
 
I don't understand, wouldn't that be illegal to do?
 
vantz said:
I don't understand, wouldn't that be illegal to do?

Yes, it would. But Compuchip meant to do a u-substitution. u=(-x), du=(-dx).
 
Exactly. And don't forget the integration boundaries as well.
 
I have it now. Thank you
 

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