解方程组
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>> a1=0.26644;a2=0.46409;a3=0.63554;a4=0.86384;b1=107.72771;b2=96.68265;b3=96.06903;b4=100.47939;>> syms c1 c2 c3
equation1=sym('((exp(-c1*a1)+a1^c2)*(1-exp(c3*a1)))/((exp(-c1*a2)+a2^c2)*(1-exp(c3*a2)))=b1/b2');
equation2=sym('((exp(-c1*a1)+a1^c2)*(1-exp(c3*a1)))/((exp(-c1*a3)+a3^c2)*(1-exp(c3*a3)))=b1/b3');
equation3=sym('((exp(-c1*a1)+a1^c2)*(1-exp(c3*a1)))/((exp(-c1*a4)+a4^c2)*(1-exp(c3*a4)))=b1/b4');
=solve(equation1,equation2,equation3,'c1','c2','c3')
Warning: Explicit solution could not be found.
> In solve at 98
c1 =
[ empty sym ]
c2 =
[]
c3 =
[] 数值解法应该没问题；a1=0.26644;a2=0.46409;a3=0.63554;a4=0.86384;b1=107.72771;b2=96.68265;b3=96.06903;b4=100.47939;
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;
((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;
((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];
= fsolve(F,rand(1,3))x =
8.6381 15.9119 7.5123
fval =
1.0e-006 *
-0.2240
-0.3869
0.1114 本帖最后由 zccbest 于 2012-6-18 07:39 编辑
google一下超越方程 多谢二位！
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