解方程组

笑熬浆糊

求解方程组中的C1,C2,C3的值？但是算出来的结果是空解，请高手看一看哪里出了问题

1. >> a1=0.26644;a2=0.46409;a3=0.63554;a4=0.86384;b1=107.72771;b2=96.68265;b3=96.06903;b4=100.47939;
   
2. >> syms c1 c2 c3
   
3. equation1=sym('((exp(-c1*a1)+a1^c2)*(1-exp(c3*a1)))/((exp(-c1*a2)+a2^c2)*(1-exp(c3*a2)))=b1/b2');
   
4. equation2=sym('((exp(-c1*a1)+a1^c2)*(1-exp(c3*a1)))/((exp(-c1*a3)+a3^c2)*(1-exp(c3*a3)))=b1/b3');
   
5. equation3=sym('((exp(-c1*a1)+a1^c2)*(1-exp(c3*a1)))/((exp(-c1*a4)+a4^c2)*(1-exp(c3*a4)))=b1/b4');
   
6. [c1,c2,c3]=solve(equation1,equation2,equation3,'c1','c2','c3')
   
7. Warning: Explicit solution could not be found.
   
8. > In solve at 98
   
9. 
   
10. c1 =
    
11. 
    
12. [ empty sym ]
    
13. 
    
14. 
    
15. c2 =
    
16. 
    
17.      []
    
18. 
    
19. 
    
20. c3 =
    
21. 
    
22.      []

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liuyalong008

数值解法应该没问题；

1. a1=0.26644;a2=0.46409;a3=0.63554;a4=0.86384;b1=107.72771;b2=96.68265;b3=96.06903;b4=100.47939;
   
2. F=@(x)[((exp(-x(1).*a1)+a1.^x(2)).*(1-exp(x(3).*a1)))./((exp(-x(1).*a2)+a2.^x(2)).*(1-exp(x(3).*a2)))-b1/b2;
   
3.    ((exp(-x(1).*a1)+a1.^x(2)).*(1-exp(x(3).*a1)))./((exp(-x(1).*a3)+a3.^x(2)).*(1-exp(x(3).*a3)))-b1/b3;
   
4.    ((exp(-x(1).*a1)+a1.^x(2)).*(1-exp(x(3).*a1)))./((exp(-x(1).*a4)+a4.^x(2)).*(1-exp(x(3).*a4)))-1/b4];
   
5. [x,fval] = fsolve(F,rand(1,3))

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1. x =
   
2. 
   
3.     8.6381   15.9119    7.5123
   
4. 
   
5. 
   
6. fval =
   
7. 
   
8.   1.0e-006 *
   
9. 
   
10.    -0.2240
    
11.    -0.3869
    
12.     0.1114

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zccbest

google一下超越方程

笑熬浆糊

多谢二位！