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after doing Laplace transform for this:

[tex] f(t) = e^{(7+5j)t}u(t-1) [/tex]

where u(t) = 1 for t >= 0 and 0 otherwise;

so here's what I have:

[tex]L[f(t)] = \frac {e^{-(s-7-5j)}}{s-7-5j} [/tex]

so, my reasoning was that it would converge if Re > 7 because that's the value for which exponential would converge. But why exactly do we not care about Im? I know that by Euler's formula, it [tex]e^{jw}[/tex] would just be oscillating but don't I need a condition for denominator of L[f(t)]?

Thanks for your time and explanation.

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# Region of convergence

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