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yunbin55

新虫 (初入文坛)

[求助] 二阶微分方程求解?

图中x为t的函数,该方程是否有解析解?若没有,能否用matlab得到数值解。新人木有金币,希望各位大虾帮忙。
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shengjunjie

木虫 (正式写手)

你好,你做出来了吗,我也遇到这样的问题了
好好学习,多运动,多发Paper...
2楼2012-04-16 13:26:02
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dbb627

荣誉版主 (著名写手)

【答案】应助回帖

感谢参与,应助指数 +1
>> dsolve('A*D2X+log(X)-X/b^2=exp(-a*t)/K+log(a^2)+1','t')
Warning: Explicit solution could not be found.
> In dsolve at 101

ans =

[ empty sym ]
matlab求不出解析解,不过数值解肯定可以,需要给初值或者边值条件
The more you learn, the more you know, the more you know, and the more you forget. The more you forget, the less you know. So why bother to learn.
3楼2012-04-16 14:08:22
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laosam280

禁虫 (正式写手)

感谢参与,应助指数 +1
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4楼2012-04-16 21:31:19
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junliwang

银虫 (初入文坛)

【答案】应助回帖

感谢参与,应助指数 +1
挺复杂的,现在还不能回答,研究一两天再回答吧,哈
5楼2012-04-27 08:46:17
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