2楼: Originally posted by xiuyouxu at 2012-04-13 17:23:46:
建议采用牛顿迭代法，不过积分部分的计算还是比较麻烦，没办法，只能用数值积分方法求解。

LoopConstant Q=[1000,5000,10000,50000];
Constant c1=3.741832E-16,c2=1.438786E-2, sigma=5.6688e-008,
         lambda1=2.5*1e-6;
Function Q=sigma*T^4-int(c1*x^(-5)/(exp(c2/(x*T))-1),x=lambda1,1E8);

c1:=3.741832E-16:
>  c2:=1.438786E-2:
>  sigma:=5.6688e-008:            ##斯特潘常数σ
>  lambda1:=2.5*1e-6:              #积分下限 λ1
> eqn:='Q=sigma*T^4-int(c1*lambda^(-5)/(exp(c2/(lambda*T)-1)),lambda=lambda1..infinity)';

Q:=1000:
> sol:=T=fsolve(Q=sigma*T^4-int(c1*lambda^(-5)/(exp(c2/(lambda*T)-1)),lambda=lambda1..infinity),T);
> eval(eqn,sol);
> eval(eqn,T= -364.440988765583);