推 ntust661:令 z = y' - y 就好 01/01 17:54
(a)Find third-order constant coefficient linear differential equation
which has the following funtion as a solution
x
y= Ae + Bcos(x) ; A,BεR
(b)Find secind-order constant coefficient linear differential equation
which has the following funtion given in (a) as a solution
三階我還記得怎麼算
根: 1 ,±i
2
∴可另(D-1)(D + 1)=0
(3)
=> y - y" + y - 1 =0
這樣我算的答案應該沒錯吧?
那麼怎麼簡化成2階呢?
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