[理工] [工數][拉式]

[asdf322505 ()]

http://www.wretch.cc/album/show.php?i=a85038862&b=2&f=1916314543&p=2

請問第4該怎嚜算呀?

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推 dapouchi:r(t) = [ u(t-1)-u(t-2) ] (t-1)
→ dapouchi:其中 u(t-2) (t-1)  換成 u(t-2) [(t-2)+ 1 ]
→ dapouchi:剩下就自己拉一拉吧！
→ asdf322505:感謝大大的回答