24小时热门版块排行榜    

查看: 1451  |  回复: 11
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

denmarkrico

银虫 (小有名气)

[求助] 求解高次复杂函数 已有3人参与

求解下面这个高次方程时为什么总是得到虚数解,我所用的是MATLAB2012b版

syms h c l theta11 theta21 theta31 x
h=14.5;
l=55.5;
c=19.73;
theta11=0.01/37;
theta21=0.035/37;
theta31=0.065/37;
F=((3*c + 3*h - (433*l)/250 + 2*l*cos(theta11) +3^(1/2)*c*sin(theta0) - c*cos(theta0) +l*cos(theta21) + 3^(1/2)*l*sin(theta21) + (2*c*(x^2 - 1))/(x^2 + 1))*(2*l^2*(sin(theta11) - 1) - 2*l^2*(sin(theta31) - 1) + 2*c*(c + h) - 2*c*l*cos(theta11) - 2*l*cos(theta11)*(c + h) + 2*l*cos(theta31)*(c + h) + 2*c*l*cos(theta0)*cos(theta31) - 2*c*l*sin(theta0)*sin(theta31) - (4*c*l*x)/(x^2 + 1) + (2*c*(c + h)*(x^2 - 1))/(x^2 + 1)) + (3*c + 3*h + (433*l)/250 + 2*l*cos(theta11) + l*cos(theta31) - c*cos(theta0) - 3^(1/2)*c*sin(theta0) - 3^(1/2)*l*sin(theta31) + (2*c*(x^2 - 1))/(x^2 + 1))*(2*l^2*(sin(theta21) - 1) - 2*l^2*(sin(theta11) - 1) - 2*c*(c + h) + 2*c*l*cos(theta11) + 2*l*cos(theta11)*(c + h) - 2*l*cos(theta21)*(c + h) + (4*c*l*x)/(x^2 + 1) - (2*c*(c + h)*(x^2 - 1))/(x^2 + 1) + (4*c*l*x*sin(theta21))/(x^2 + 1) + (2*c*l*cos(theta21)*(x^2 - 1))/(x^2 + 1)))^2 + (((433*c)/250 + (433*h)/250 + 3*l + 2*l*sin(theta11) + 2*l*sin((2*pi)/3 + theta21) - (2*c*x)/(x^2 + 1) - (3^(1/2)*c*(x^2 - 1))/(x^2 + 1))*(2*l^2*(sin(theta11) - 1) - 2*l^2*(sin(theta31) - 1) + 2*c*(c + h) - 2*c*l*cos(theta11) - 2*l*cos(theta11)*(c + h) + 2*l*cos(theta31)*(c + h) - (4*c*l*x)/(x^2 + 1) + (2*c*(c + h)*(x^2 - 1))/(x^2 + 1) + (4*c*l*x*sin(theta31))/(x^2 + 1) - (2*c*l*cos(theta31)*(x^2 - 1))/(x^2 + 1)) - ((433*c)/250 + (433*h)/250 - 3*l + 2*l*sin(theta11) +c*sin(theta0) + l*sin(theta31) + 3^(1/2)*l*cos(theta31) - 3^(1/2)*c*cos(theta0) + (4*c*x)/(x^2 + 1))*(2*l^2*(sin(theta21) - 1) - 2*l^2*(sin(theta11) - 1) - 2*c*(c + h) + 2*c*l*cos(theta11) + 2*l*cos(theta11)*(c + h) - 2*l*cos(theta21)*(c + h) + (4*c*l*x)/(x^2 + 1) - (2*c*(c + h)*(x^2 - 1))/(x^2 + 1) + (4*c*l*x*sin(theta21))/(x^2 + 1) + (2*c*l*cos(theta21)*(x^2 - 1))/(x^2 + 1)))^2 + ((3*c + 3*h - (433*l)/250 + 2*l*cos(theta11) + l*cos(theta21) - c*cos(theta0) + 3^(1/2)*c*sin(theta0) + 3^(1/2)*l*sin(theta21) + (2*c*(x^2 - 1))/(x^2 + 1))*((433*c)/250 + (433*h)/250 - 3*l + 2*l*sin(theta11) +c*sin(theta0) + l*sin(theta31) + 3^(1/2)*l*cos(theta31) - 3^(1/2)*c*cos(theta0) + (4*c*x)/(x^2 + 1)) + (3*c + 3*h + (433*l)/250 + 2*l*cos(theta11) + l*cos(theta31) - c*cos(theta0) - 3^(1/2)*c*sin(theta0) - 3^(1/2)*l*sin(theta31) + (2*c*(x^2 - 1))/(x^2 + 1))*((433*c)/250 + (433*h)/250 + 3*l - 2*l*sin(theta11) + 3^(1/2)*l*cos(theta21) - l*sin(theta21) - c*sin(theta0) - 3^(1/2)*c*cos(theta0) - (4*c*x)/(x^2 + 1)))^2*(2*c*h - 2*l^2*(sin(theta11) - 1) + 2*c^2 - 2*c*(c + h) + 2*c*l*cos(theta11) + 2*l*cos(theta11)*(c + h)) + ((((433*c)/250 + (433*h)/250 - 3*l + 2*l*sin(theta11) +c*sin(theta0) + l*sin(theta31) + 3^(1/2)*l*cos(theta31) - 3^(1/2)*c*cos(theta0) + (4*c*x)/(x^2 + 1))*(2*l^2*(sin(theta11) - 1) - 2*l^2*(sin(theta21) - 1) + 2*c*(c + h) - 2*c*l*cos(theta11) - 2*l*cos(theta11)*(c + h) + 2*l*cos(theta21)*(c + h) + 2*c*l*cos(theta0)*cos(theta21) - 2*c*l*sin(theta0)*sin(theta21) - (4*c*l*x)/(x^2 + 1) + (2*c*(c + h)*(x^2 - 1))/(x^2 + 1)) + ((433*c)/250 + (433*h)/250 + 3*l - 2*l*sin(theta11) + 3^(1/2)*l*cos(theta21) - l*sin(theta21) - c*sin(theta0) - 3^(1/2)*c*cos(theta0) - (4*c*x)/(x^2 + 1))*(2*l^2*(sin(theta11) - 1) - 2*l^2*(sin(theta31) - 1) + 2*c*(c + h) - 2*c*l*cos(theta11) - 2*l*cos(theta11)*(c + h) + 2*l*cos(theta31)*(c + h) + 2*c*l*cos(theta0)*cos(theta31) - 2*c*l*sin(theta0)*sin(theta31) - (4*c*l*x)/(x^2 + 1) + (2*c*(c + h)*(x^2 - 1))/(x^2 + 1)))*(2*c + 2*h + 2*l*cos(theta11) + (2*c*(x^2 - 1))/(x^2 + 1)) - ((3*c + 3*h + (433*l)/250 + 2*l*cos(theta11) + l*cos(theta31) - c*cos(theta0) - 3^(1/2)*c*sin(theta0) - 3^(1/2)*l*sin(theta31) + (2*c*(x^2 - 1))/(x^2 + 1))*(2*l^2*(sin(theta11) - 1) - 2*l^2*(sin(theta21) - 1) + 2*c*(c + h) - 2*c*l*cos(theta11) - 2*l*cos(theta11)*(c + h) + 2*l*cos(theta21)*(c + h) + 2*c*l*cos(theta0)*cos(theta21) - 2*c*l*sin(theta0)*sin(theta21) - (4*c*l*x)/(x^2 + 1) + (2*c*(c + h)*(x^2 - 1))/(x^2 + 1)) - (3*c + 3*h - (433*l)/250 + 2*l*cos(theta11) +l*cos(theta21) - c*cos(theta0) + 3^(1/2)*c*sin(theta0) + 3^(1/2)*l*sin(theta21) + (2*c*(x^2 - 1))/(x^2 + 1))*(2*l^2*(sin(theta11) - 1) - 2*l^2*(sin(theta31) - 1) + 2*c*(c + h) - 2*c*l*cos(theta11) - 2*l*cos(theta11)*(c + h) + 2*l*cos(theta31)*(c + h) + 2*c*l*cos(theta0)*cos(theta31) - 2*c*l*sin(theta0)*sin(theta31) - (4*c*l*x)/(x^2 + 1) + (2*c*(c + h)*(x^2 - 1))/(x^2 + 1)))*(2*l*sin(theta11) - 2*l + (4*c*x)/(x^2 + 1)))*((3*c + 3*h - (433*l)/250 + 2*l*cos(theta11) + l*cos(theta21) + 3^(1/2)*l*sin(theta21) + (3*c*(x^2 - 1))/(x^2 + 1) + (2*3^(1/2)*c*x)/(x^2 + 1))*((433*c)/250 + (433*h)/250 - 3*l + 2*l*sin(theta11) - l*sin(theta31) + 3^(1/2)*l*cos(theta31) + (2*c*x)/(x^2 + 1) - (3^(1/2)*c*(x^2 - 1))/(x^2 + 1)) + (3*c + 3*h + (433*l)/250 + 2*l*cos(theta11) + l*cos(theta31) - c*cos(theta0) - 3^(1/2)*c*sin(theta0) - 3^(1/2)*l*sin(theta31) + (2*c*(x^2 - 1))/(x^2 + 1))*((433*c)/250 + (433*h)/250 + 3*l - 2*l*sin(theta11) + 3^(1/2)*l*cos(theta21) - l*sin(theta21) - c*sin(theta0) - 3^(1/2)*c*cos(theta0) - (4*c*x)/(x^2 + 1)));
回复此楼

» 猜你喜欢

» 本主题相关价值贴推荐,对您同样有帮助:

心 那个凉啊
已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖

paopaoai11

木虫 (小有名气)

你这什么方程啊?

[ 发自小木虫客户端 ]
泡泡
4楼2013-12-14 01:03:00
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 12 个回答

feixiaolin

荣誉版主 (文坛精英)

优秀版主

【答案】应助回帖

感谢参与,应助指数 +1
1)theta0 待求还是已知?
2)取y1=(x^2 - 1))/(x^2 + 1);
        y2=x/(x^2 + 1);
     先求y1, y2,最后求 x如何?

» 本帖已获得的红花(最新10朵)

2楼2013-12-13 22:53:29
已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖

jerkwin

专家顾问 (正式写手)

你这方程, 能解出来我觉得很奇怪
3楼2013-12-13 23:10:14
已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖

ynod23

金虫 (小有名气)

【答案】应助回帖

感谢参与,应助指数 +1
函数没有看完,瞎了。。。
我认为,这种情况,不是查程序哪儿出问题了,而应该看方法对不对。。。。
先试试看能不能把那个大函数写成许多函数相互运算的结果,这样就降低了出错的可能。如果这样还有问题的话,也可以根据matlab的运行提示,找出是哪一行的问题。这样把问题的规模缩小,我觉得比较靠谱。
希望能帮到你。

» 本帖已获得的红花(最新10朵)

5楼2013-12-14 04:43:11
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] 能源材料化学课题组招收硕士研究生8-10名 +3 脱颖而出 2026-03-16 6/300 2026-03-17 21:19 by z1z2z3879
[考研] 341求调剂 +5 捣蛋猪猪 2026-03-11 7/350 2026-03-17 19:09 by 捣蛋猪猪
[考研] 考研化学学硕调剂,一志愿985 +4 张vvvv 2026-03-15 6/300 2026-03-17 17:15 by ruiyingmiao
[考研] 332求调剂 +6 Zz版 2026-03-13 6/300 2026-03-17 17:03 by ruiyingmiao
[考研] 一志愿南京大学,080500材料科学与工程,调剂 +4 Jy? 2026-03-16 4/200 2026-03-17 11:02 by gaoqiong
[硕博家园] 深圳大学硕士招生(2026秋,传感器方向,仅录取第一志愿) +4 xujiaoszu 2026-03-11 9/450 2026-03-17 10:29 by xujiaoszu
[考研] 0854控制工程 359求调剂 可跨专业 +3 626776879 2026-03-14 9/450 2026-03-16 17:42 by 626776879
[考研] 环境工程调剂 +6 大可digkids 2026-03-16 6/300 2026-03-16 17:16 by barlinike
[考研] 304求调剂 +3 曼殊2266 2026-03-14 3/150 2026-03-16 16:39 by houyaoxu
[考研] 070300化学学硕求调剂 +6 太想进步了0608 2026-03-16 6/300 2026-03-16 16:13 by kykm678
[考研] 285求调剂 +6 ytter 2026-03-12 6/300 2026-03-16 15:05 by njzyff
[考研] 中科大材料与化工319求调剂 +3 孟鑫材料 2026-03-14 3/150 2026-03-14 20:10 by ms629
[考研] 材料与化工 323 英一+数二+物化,一志愿:哈工大 本人本科双一流 +4 自由的_飞翔 2026-03-13 5/250 2026-03-14 19:39 by hmn_wj
[考研] 求调剂(材料与化工327) +4 爱吃香菜啦 2026-03-11 4/200 2026-03-13 22:11 by JourneyLucky
[考研] 材料工程调剂 +9 咪咪空空 2026-03-12 9/450 2026-03-13 22:05 by 星空星月
[考研] 0703化学一志愿211 总分320求调剂 +5 玛卡巴卡啊哈 2026-03-11 5/250 2026-03-13 21:40 by JourneyLucky
[考研] (081700)化学工程与技术-298分求调剂 +12 11啦啦啦 2026-03-11 35/1750 2026-03-13 21:25 by JourneyLucky
[考研] 【考研调剂求收留】 +3 Ceciilia 2026-03-11 3/150 2026-03-13 20:18 by JourneyLucky
[考研] 328化工专硕求调剂 +4 。,。,。,。i 2026-03-12 4/200 2026-03-13 14:44 by JourneyLucky
[考研] 270求调剂 085600材料与化工专硕 +3 YXCT 2026-03-11 3/150 2026-03-13 10:13 by houyaoxu
信息提示
请填处理意见