作者smallprawn (水中瑕)
看板Grad-ProbAsk
标题[理工] [工数]-拉式转换
时间Sun Jan 24 13:29:40 2010
L{(cos t)u(t-π/2)}=L{-(sin(t-π/2)u(t-π/2)}
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为什麽第二步不是 L{cos(t-π/2)u(t-π/2)}
除了尤拉判断以外.他的判断依据又可以是什麽?!
如果变成L{(cos t)u(t-3π/2)}=L{(_____(t-3π/2))u(t-3π/2)}
或者L{(sin t)u(t-π/2)}=L{(_____(t-π/2))u(t-π/2)}
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1F：→ smallprawn:ㄜ..是我问的太奇怪吗= =.. 01/24 14:44