推 fatfatyu:謝謝大大的解答 03/15 17:53
推 ntust661:Great 03/15 19:56
※ 引述《fatfatyu (泡麵王)》之銘言：
: http://uploadpie.com/4josy
: 請問1小題成立的條件為何?
: 3小題該如何證明?
: 4小題,在下找不到運算子的解,麻煩強手幫在下看一下
4 3 2
4. D + 2D + 3D + 2D + 1 = 0
2 2 2
D *(D +2D +1) + 2D + 2D +1 = 0
2 2
D *(D+1) + 2D(D+1) +1 = 0
2 2 2
[D*(D+1) + 1] = (D + D + 1) = 0
2 2
[(D+1/2) + 3/4 ] = 0
-(1/2)x 3^(1/2) -(1/2)x 3^(1/2)
yh = (c1+c2x) e cos———－x + (c3+c4x) e sin————x
2 2
有錯請告知...
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