Integral of unit impulse function?

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The integral of the unit impulse function, represented as ∫δ(t) dt, equals 1, being nonzero only at t = 0. When integrating a product like ∫δ(t) e-jωt, the evaluation simplifies to e0, which is also 1, due to the delta function's behavior at t = 0. The discussion raises a question about the necessity of integrating over limits, suggesting a potential misunderstanding of the delta function's properties. The key takeaway is that the integral of δ(t) multiplied by another function f(t) results in f(0), reinforcing the delta function's role in distribution theory. Understanding this concept is crucial for applying the delta function in various mathematical and engineering contexts.
Abdulwahab Hajar
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Homework Statement



let's use this symbol to denote the unit impulse function δ
When integrating the unit impulse function (from negative infinity to infinity) ∫δ(t) dt I know that this results in a value of 1 and is only nonzero at the point t = 0.

However for example take this integral into consideration ∫δ(t) e-jωt
since the delta function is only nonzero at the point zero, we only evaluate this multiplication at the point 0 which yields e0 which is 1.

but how can we do that, the integral involves two functions dependant on time shouldn't we integrate from limits for example 0- to 0+ and integrate it by parts or something like that?

Homework Equations



∫δ(t) = 1 at t =0

The Attempt at a Solution



My attempt is attempting to explain it above
Thank you
 
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There are a few different ways to put the Derac delta function (generalized function, distribution) on a solid theoretical basis (see https://en.wikipedia.org/wiki/Dirac_delta_function). The result and goal of all of them is that ∫δ(t)f(t)dt = f(0).
 
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FactChecker said:
There are a few different ways to put the Derac delta function (generalized function, distribution) on a solid theoretical basis (see https://en.wikipedia.org/wiki/Dirac_delta_function). The result and goal of all of them is that ∫δ(t)f(t)dt = f(0).
thank you, you were very helpful...
loving the profile pic btw!
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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