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[求助]这个函数的积分怎么求?

hanzhanyong 发布于 2006-12-01 19:40, 2478 次点击

bb =-133114455017668875/18014398509481984/(42429-17300*cos(g))^(1/2)-7454409480989457/36028797018963968*log(-1+1/100*(42429-17300*cos(g))^(1/2))+52180866366926199/180143985094819840*log(3+1/100*(122429-17300*cos(g))^(1/2))+133114455017668875/18014398509481984*(6/(32429/10000-173/100*cos(g))-47/5)/(122429-17300*cos(g))^(1/2)+83196534386043046875/1125899906842624*(32429/5000-173/50*cos(g)-54/(32429/10000-173/100*cos(g)))/(122429-17300*cos(g))^(3/2)
求对g在0到pi的积分
int(bb,g,0,pi)
Warning: Explicit integral could not be found.
> In D:\MATLAB6p5\toolbox\symbolic\@sym\int.m at line 58
quad(bb,0,pi)
??? Error using ==> fcnchk
If FUN is a MATLAB object, it must have an feval method.

Error in ==> D:\MATLAB6p5\work\quad.m
On line 52 ==> f = fcnchk(funfcn);
quadl(bb,0,pi)
??? Error using ==> fcnchk
If FUN is a MATLAB object, it must have an feval method.

Error in ==> D:\MATLAB6p5\toolbox\matlab\funfun\quadl.m
On line 51 ==> f = fcnchk(funfcn);

3 回复
#2
abingchem2006-12-01 20:55
syms g
>> bb =-133114455017668875/18014398509481984/(42429-17300*cos(g))^(1/2)-7454409480989457/36028797018963968*log(-1+1/100*(42429-17300*cos(g))^(1/2))+52180866366926199/180143985094819840*log(3+1/100*(122429-17300*cos(g))^(1/2))+133114455017668875/18014398509481984*(6/(32429/10000-173/100*cos(g))-47/5)/(122429-17300*cos(g))^(1/2)+83196534386043046875/1125899906842624*(32429/5000-173/50*cos(g)-54/(32429/10000-173/100*cos(g)))/(122429-17300*cos(g))^(3/2);
>> int(bb,g,0,pi)
Warning: Explicit integral could not be found.
> In C:\MATLAB6p5\toolbox\symbolic\@sym\int.m at line 58
ans =
int(-8319653438604305/1125899906842624/(42429-17300*cos(g))^(1/2)-7454409480989457/36028797018963968*log(-1+1/100*(42429-17300*cos(g))^(1/2))+1304521659173155/4503599627370496*log(3+1/100*(122429-17300*cos(g))^(1/2))+(24958960315812915/562949953421312/(32429/10000-173/100*cos(g))-78204742322880467/1125899906842624)/(122429-17300*cos(g))^(1/2)+(32934331220764036483/68719476736000-175695806259587971/687194767360*cos(g)-137103663844187145/34359738368/(32429/10000-173/100*cos(g)))/(122429-17300*cos(g))^(3/2),g = 0 .. pi)
>> vpa(ans,4)
ans =
1.033
#3
hanzhanyong2006-12-01 21:02

太谢谢了,阿拉真主赞美你!!!

#4
hanzhanyong2006-12-01 21:03

这个问题,我一直就解决不了,今天真是碰到高人了

1