Re: [理工] [離散] 100清大資工

看板Grad-ProbAsk作者BigTora (大虎)時間14年前 (2012/02/03 17:16)推噓1(1推 0噓 2→)

留言3則, 3人參與討論串2/2 (看更多)

※ 引述《PrettyPingzi (Pingzi)》之銘言： : 15.There are two kinds of particles insides a nuclear reactor. In erery : second, an "A" particle will spilts into three "B" particles,and a "B" : will spilts into an "A" particles and two "B" particles. If there is a : single "A" particles in the reactor at t=0, how many particles are there : altogether at t=100? : 這題我對遞回的定義不知道該怎麼去訂 : 我看黃子嘉的解題書是 A(t)=B(t-1) : B(t)=3A(t-1)+2B(t-1) : A(0)=1 ,B(O)=0 : B一次分裂不是分1A2B嗎??? 那上述的遞回定義怎跑出來的囧 : 還是我想的地方有問題??? : 有請板友幫忙了感激不盡^^ 因為A會變成3個B，而B會變成1A2B t = 0假如有x個A，y個B， t = 1就會有y個A，3x + 2y個B，所以A(t) = B(t - 1) B(t) = 3A(t - 1) + 2B(t - 1) 不過自己覺得這題用對角化解比較簡單 @@ ┌ ┐ 令A = │0 1│ │3 2│ └ ┘ 100 ┌ ┐ ┌ ┐ │0 1│ │1│ 就是答案了 │3 2│ │0│ └ ┘ └ ┘ -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 118.166.116.101

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sb107912

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BigTora

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