This series is convergent and coincides with f(x)

For practical purposes we transform the Fourier-Stieltjes Integral into the conventional form and remember the Dirichlet conditions

Then in the unified conditions we have

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Therefore, Edward Whittakker finally in 1964 year formulate this statement in his book

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The basic statement of the Nyquist theorem.

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ЛДС – линейная

дискретная система

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