数学建模 malab第四章作业 .doc

数学建模习题4作业第2题(1)程序如下：a=2.0079,0.1855,2.0079*155.79/(2.0079-0.1855);f=(t)a(3).*(exp(-a(2).*t)-exp(-a(1).*t);g=(t)-f(t);h_1=(t)f(t)-20;h_2=(t)f(t)-80;smax,fval=fminbnd(g,0,20)x1=fzero(h_1,0,smax)x2=fzero(h_2,0,smax)x3=fzero(h_1,smax,20)x4=fzero(h_2,smax,20)运行结果：smax = 1.3069fval = -122.2501x1 = 0.0689x2 = 0.3805x3 = 11.5887x4 =4.1125(2)程序如下：a=2.0079,0.1855,3/4*103.86,0,0,0,0,0,0,0;a(4)=a(3)/(