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- Thread starter gomes.
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vela

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vela

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thanks, but how would i integrate u(t+4)e^[t(-1-iw)-4]?

How do i deal with the u(t+4)?

How do i deal with the u(t+4)?

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vela

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What is u(t+4) equal to for t>-4?

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sorry im really stuck, u(t)?

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vela

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http://www.efunda.com/math/unit_delta/unit_delta.cfm

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vela

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Well, the first line definitely doesn't equal the second line.

The integrals look okay.

The integrals look okay.

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vela

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[tex]u(t) \ne \int_{-\infty}^\infty u(t+4) e^{t(-1-i\omega)-4}\,dt[/tex]

The integral in the second line is fine to calculate the Fourier transform you're looking for, but it's definitely not equal to u(t) as you wrote.

Try the substitution t'=t+4 to evaluate the integral.

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thanks! got it now

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