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Sketch the time functions given. Then use the definition of the Laplace transform, (7.4), and the table of integrals in Appendix A to calculate the Laplace transforms of the time functions.

5u(t - 2)

User Osnoz
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Final answer:

To calculate the Laplace transform of the function 5u(t - 2), we sketch the time function, recognize the effects of the unit step function, and utilize the table of Laplace transforms to find that the transform is 5e^{-2s}/s.

Step-by-step explanation:

The question involves calculating the Laplace transform of a given time function 5u(t - 2), where u(t - 2) is the unit step function that shifts to the right by 2 units on the time axis. To sketch this function, we plot a graph that is zero for t < 2 and becomes 5 for t ≥ 2. After sketching, we use the definition of the Laplace transform to transform the time function into the s-domain.

The Laplace transform of 5u(t - 2) is given by:

Recognize that the step function shift results in the multiplication of the function by e^{-2s} in the s-domain.

Identify the Laplace transform of the unit step function u(t) from the table which is \frac{1}{s}.

Account for the scaling factor of 5 and the shift of 2 to find the Laplace transform L{5u(t - 2)} = 5e^{-2s}/s.

User Pratik Lad
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