24小时热门版块排行榜    

查看: 1745  |  回复: 7
当前只显示满足指定条件的回帖,点击这里查看本话题的所有回帖

duyang2012

铜虫 (小有名气)

[求助] 一个数学积分求解 已有1人参与

遇到一个积分求解的问题(积分公式见截图),自己一直试图用数值计算的方法求解,但最终不得其解。跪求大神解答!!!

一个数学积分求解
积分求解.png
回复此楼

» 收录本帖的淘帖专辑推荐

数学问题集锦

» 猜你喜欢

» 本主题相关价值贴推荐,对您同样有帮助:

已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖

feixiaolin

荣誉版主 (文坛精英)

优秀版主

引用回帖:
3楼: Originally posted by duyang2012 at 2015-01-11 17:34:54
不懂,可以说详细一点吗,谢谢!!!...

取 u=1/x,  v=1/a

[ 发自小木虫客户端 ]
4楼2015-01-11 18:27:55
已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖
查看全部 8 个回答

feixiaolin

荣誉版主 (文坛精英)

优秀版主

【0, inf】积分区间映射到【0, 1】,然后再数值求解。
2楼2015-01-11 17:20:32
已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖

duyang2012

铜虫 (小有名气)

引用回帖:
2楼: Originally posted by feixiaolin at 2015-01-11 17:20:32
【0, inf】积分区间映射到【0, 1】,然后再数值求解。

不懂,可以说详细一点吗,谢谢!!!
3楼2015-01-11 17:34:54
已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖

pippi6

铁杆木虫 (著名写手)

工程和科学数值计算咨询

【答案】应助回帖

★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★
感谢参与,应助指数 +1
duyang2012: 金币+20, ★★★★★最佳答案, 完美解决问题 2015-01-12 11:10:45
我用maple 7
> f:=BesselI(0, alpha*x)*alpha*exp(-alpha^2)*x*exp(-(x^2+alpha^2)/2)
> *(1-exp(-x^2/2))^1022;

> s:=int(int(f,alpha=0..infinity),x=0..infinity);
  s := 3299122687584745137204367643230771106304997323142764671919892526213274482351735424595090152580805831487201081992151782359365957048266356808329891738576418898384550273099110184494910603827424479869838674181059409833013059735407792907696592569535276701736861158593056561375652527873922258647738643928389281331366095207532193114305843094745273866336452296051523189325911545359997748735545153365459326965824504140992990653748551563388621812295143879168563643028714331800616525107242938555105725864904443179487735448344512225826058337229629080065151365167343274055473303802181974301995992231288914893936583978868212030806302235382565661039319775858591452481276532369619717771944703319704609243884667963269698910969623461539798686254883/741993016396956735405613435356683782697512283069823991064277931426980443824577566664069913413257621498538182516652902989918523185791709453919677031772399696514284422802749913157553979575003207665736459377430450383919221006176370669384465219743309411041792052666184021088982010598590366702909953828519058138526150106114448075948267632468571674052634702160284009616244631715592753300091481834250539282210722819840060174111768646004068650228726292470427652007163617929736425185577083563672618801965072487519722221379722725217400914053294087849015460578362361120445241591716408147719927671948668690922637069198489929597905348227031903643587457869031130741184797205245991710558088926873306205286102419574747370548119522443416892882892800

数值
> evalf[15](s);
                          .00444629883931381
不知道是否是你期待的
5楼2015-01-11 19:09:55
已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖
最具人气热帖推荐 [查看全部] 作者 回/看 最后发表
[考研] 售一区SCI文章T0P,我:8O.551.O54,科目全,可十急 +6 ncTVBM6AOJHF 2026-11-04 16/800 2026-11-06 07:55 by GBJlw5zzHWpZ
[考博] 售SCI一区文章,我:8.O.55.1.O.54,科目齐全,可伽急 +8 ncTVBM6AOJHF 2026-11-04 20/1000 2026-11-06 07:55 by GBJlw5zzHWpZ
[硕博家园] 售SCI一区T0P文章,我:8O.55.1.O.54,科目全,可伽急 +6 ncTVBM6AOJHF 2026-11-04 12/600 2026-11-06 07:55 by GBJlw5zzHWpZ
[公派出国] 售SCI一区T0P文章,我:8.O.55.1.O.5.4,科目全,可+急 +3 PYZmcHr5kSaq 2026-11-05 8/400 2026-11-06 06:16 by qL1cU46YIdK0
[考博] 售SCI一区文章,我:8O5.5.1.O5.4,科目全,可伽急 +3 ELBZ6WwEaRj6 2026-11-05 5/250 2026-11-06 05:54 by qL1cU46YIdK0
[考研] 售SCI一区文章,我:8.O.551.O.5.4,科目全,可伽急 +3 ELBZ6WwEaRj6 2026-11-04 10/500 2026-11-06 05:32 by qL1cU46YIdK0
[公派出国] 售SCI一区T0P文章,我:8.O.55.1.O.54,科目齐全,可+急 +3 ttH3f1oA6ace 2026-11-04 8/400 2026-11-06 05:22 by qL1cU46YIdK0
[公派出国] 售SCI一区文章,我:8.O.551.O.5.4,科目全,可伽急 +4 ttH3f1oA6ace 2026-11-04 10/500 2026-11-06 05:21 by qL1cU46YIdK0
[公派出国] 售SCI-T0P文章,我:8O.5.5.1.O.54,科目齐全,可+急 +7 ncTVBM6AOJHF 2026-11-04 11/550 2026-11-06 05:15 by Equinoxhua
[考研] 售SCI-T0P文章,我:8O.5.5.1.O.54,科目齐全,可+急 +4 ttH3f1oA6ace 2026-11-04 14/700 2026-11-06 05:11 by qL1cU46YIdK0
[公派出国] 售SCI文章,我:8O5.5.1.O.54,科目齐全,可+急 +7 ncTVBM6AOJHF 2026-11-04 22/1100 2026-11-06 04:47 by qL1cU46YIdK0
[公派出国] 售SCI-T0P文章,我:8O.5.5.1.O.54,科目齐全,可+急 +4 ELBZ6WwEaRj6 2026-11-04 9/450 2026-11-06 02:26 by qL1cU46YIdK0
[硕博家园] 售一区SCI文章T0P,我:8O.551.O54,科目全,可十急 +4 ELBZ6WwEaRj6 2026-11-04 8/400 2026-11-06 02:24 by qL1cU46YIdK0
[公派出国] 售SCI-T0P文章,我:8O.5.5.1.O.54,科目齐全,可+急 +3 ELBZ6WwEaRj6 2026-11-04 9/450 2026-11-06 02:15 by qL1cU46YIdK0
[考博] 售一区SCI文章T0P,我:8O.551.O54,科目全,可十急 +4 ttH3f1oA6ace 2026-11-04 7/350 2026-11-06 02:13 by qL1cU46YIdK0
[考研] 售SCI一区T0P文章,我:8.O55.1.O.54,科目全,可十急 +4 ttH3f1oA6ace 2026-11-04 10/500 2026-11-06 02:04 by qL1cU46YIdK0
[硕博家园] 售SCI-T0P文章,我:8O.5.5.1.O.54,科目齐全,可+急 +3 ttH3f1oA6ace 2026-11-04 9/450 2026-11-06 02:02 by qL1cU46YIdK0
[硕博家园] 售SCI一区T0P文章,我:8.O55.1.O.54,科目全,可十急 +4 hNpp4Y2CGvSC 2026-11-04 12/600 2026-11-06 01:53 by qL1cU46YIdK0
[硕博家园] 售SCI一区文章,我:8.O.551.O.5.4,科目全,可伽急 +5 ncTVBM6AOJHF 2026-11-04 10/500 2026-11-06 01:40 by qL1cU46YIdK0
[基金申请] 各位基础老师们,看完中央《从严治党》的决定后,对学术界更加有信心了吧 +5 iaeyuan 2026-11-01 5/250 2026-11-04 14:43 by jinchengzi
信息提示
请填处理意见