Commute of Limits and Integrals: Understanding the Relationship

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Limits do not commute, as demonstrated by testing various functions. The expression "Limit of z to A[Expression]" requires z to be a free variable, which it is not in the provided examples. This misunderstanding leads to confusion about the validity of interchanging limits. Additionally, integrals and limits do not always commute, highlighting the complexity of these mathematical operations. The discussion emphasizes the importance of understanding the roles of variables in limits and integrals.
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I was wondering if Limits commute,

Ie:
Limit of z to infinity[ Limit of z to 0[ f(0)/z ]]

=

Limit of z to 0[ Limit of z to infinity[ f(0)/z ]]

Edit: Nvm, they dont... I just did a some test functions... I'm just hoping for an easy way to finish one of my proofs.

Though on a sidenote, integrals and limits do commute right?
 
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This doesn't even make sense. The only way "Limit of z to A[Expression]" even makes sense is if z is a free variable in the Expression. But in both "Limit of z to 0[ f(0)/z ]" and "Limit of z to infinity[ f(0)/z ]", z is NOT a free variable. Note that in "f(0)/z", z is a free variable, but in "Limit of z to B[ f(0)/z ]", it is not. (In the above, A and B can of course be anything, not just 0 and infinity which you've used in your examples). So I don't see how you could have determined:

Edit: Nvm, they dont... I just did a some test functions...

since it doesn't even make sense.

And integrals and limits don't always commute.
 
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