1 -0s
L { u(t) } = ── e
s
1 -as
L { u(t - a) } = ─── e
s
L { u(at - b) } = ????
我利用定義來做
∞ -st
∫ u(at - b) e dt
0
令 v = at - b
∞ -s(v+b)/a
= ∫ u(v) e dv/a
-b
1 ∞ -(bs/a) -(s/a)v
= ── ∫ e × e dv
a 0
1 -bs/a ∞ -(s/a)v
= ── e ∫ e dv
a 0
1 -bs/a -a -(s/a)v │∞
= ── e ── e │
a s │0
1 -bs/a
= ──── e (怪怪的@@)
s
轉換回去又長不一樣了
有神人知道我哪裡做錯了嗎@@?
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