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In mathematical analysis, the initial value theorem is a theorem used to relate frequency domain expressions to the time domain behavior as time approaches zero.〔http://fourier.eng.hmc.edu/e102/lectures/Laplace_Transform/node17.html〕 It is also known under the abbreviation IVT. Let : be the (one-sided) Laplace transform of ''ƒ''(''t''). The initial value theorem then says〔Robert H. Cannon, ''Dynamics of Physical Systems'', Courier Dover Publications, 2003, page 567.〕 : == Proof == Based on the definition of Laplace transform of derivative we have: : thus: : But is indeterminate between t=0− to t=0+; to avoid this, the integration can be performed in two intervals: : =\lim_\^e^f^(t)dt" TITLE="\int_^e^f^(t)dt">) + \lim_()\} In the first expression where 0− \lim_ () &=\lim_\^f^(t)dt" TITLE="\int_^f^(t)dt">)\} + \lim_\\lim_()\}\\ &=f(t)|_^ + 0\\ &= f(0^+)-f(0^-)+0\\ \end By substitution of this result in the main equation we get: : 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「Initial value theorem」の詳細全文を読む スポンサード リンク
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