Notation issue with the integration of exponents.

AI Thread Summary
The discussion centers on the integration of the expression ∫_{0}^{∞} exp((iω - α)t) dt and the issue of applying limits correctly. The user notes that rewriting the exponent as (-(α - iω)t) yields a finite result, while the original form leads to an infinite answer. The key point is that the integral converges only when the coefficient of t in the exponent is negative, meaning that for convergence, it is essential that (iω - α) < 0. This highlights the importance of proper notation in determining the behavior of integrals at their limits. Understanding the conditions for convergence is crucial in resolving such notation issues in integration.
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I'll not go into the details of the full question, because they are irrelevant to my problem.
Basically I have to integrate
\int_{0}^{\infty} exp (\iota\omega-\alpha)t dt

Which is a nice and easy integration, but it's putting in the limits that bothers me.

I simply wrote the exponent as ((\iota \omega - \alpha)t) because I didn't feel like writing an extra minus sign. I see no reason why I could not have written it

(-( \alpha -\iota \omega )t)

Which gives a finite answer when putting in the limits, whereas the first way of writing it gives an infinite answer. Could someone explain why one of these notations are incorrect?
 
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Integral[0, inf] exp(at)dt converges, i.e., has a finite value only when a<0.
 
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