Question

醜B

為什麼這時積分變數t變換為τ時，積分範圍不會改變呢

例題1-7:
Given a function f(t) and its Laplace transform F(s), what is the Laplace transform of
the delayed version of f(t) by 2>0 units of time, i.e., f(t−2)? You must give a
+b(1)
proof of your answer.
解 根據拉氏轉換的定義,F(s)=L[f(t)]=ff(t)e="d,所以
【85 中興電機】
[ƒ (1-2)] = f(t−2) e™ dt = f(t-2)e(-) d(-2)
-2s
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0
0
C-TER
-λs
(a)D
-ST
=eft-)e-d(1-2) = e | f(t)e dt = eF(s)
0

拉氏轉換

Answer 1

✨ Best Answer ✨

峨

因為拉普拉斯假設對所有實數t>=0時 所以不是-λ到inf 是0到inf 說實在不是真的inf 是inf-λ但inf-λ趨近inf所以就inf