How Do You Integrate Absolute Values with Complex Exponentials?

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To integrate the expression ∫_{-3}^{3}|t|e^{-jωt}dt, it is necessary to consider the absolute value, which can be addressed by splitting the integral into two parts: one from 0 to 3 and another from -3 to 0. This leads to the equation ∫_{-3}^{3}|t|e^{-jωt}dt = ∫_{0}^{3}te^{-jωt}dt - ∫_{-3}^{0}te^{-jωt}dt. Another approach involves using Euler's identity to separate the integral into real and imaginary components, resulting in ∫_{-3}^{3}|t|cos(ωt)dt + j∫_{-3}^{3}|t|sin(ωt)dt. Utilizing symmetries can simplify the calculations, particularly when addressing the absolute value. Both methods effectively tackle the integration of absolute values with complex exponentials.
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Homework Statement



<br /> \int_{-3}^{3}|t|e^{-jwt}dt<br />


The Attempt at a Solution



I am not sure if I need to break this into two regions due to the abs value...
 
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Yes, that is one approach:

\int_{-3}^3 |t| e^{-j \omega t} \, dt = \int_{0}^3 t e^{-j \omega t} \, dt - \int_{-3}^0 t e^{-j \omega t} \, dt
and then you can solve both integrals with a trick (write the integrand as a derivative w.r.t. omega, for example).

Alternatively, you can use Euler's identity to write the integral as

\int_{-3}^3 |t| \cos(\omega t) \, dt + j \int_{-3}^3 |t| \sin(\omega t) \, dt
and use (anti)-symmetries to reduce the problem before taking care of the absolute value.
 
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