4楼: Originally posted by LESK乐 at 2013-10-21 16:04:49
谢谢，不过为什么我用计算器把答案带进去算出来的方程答案不对啊，http://www.ilovematlab.cn/thread-263705-1-1.html这是我之前发的帖子，里面的结果跟你的一样...

function solvenonl_Eqs
clear all;clc
x0=[0.2 0.6 0.75 1.45];
x=fsolve(@Eqs,x0)
fval=Eqs(x)

function f=Eqs(x)
x1=x(1);
x2=x(2);
x3=x(3);
x4=x(4);
f(1)=2*(cos(x1)-cos(x2)+cos(x3)-cos(x4))-1-pi/4;
f(2)=2*(cos(3*x1)-cos(3*x2)+cos(3*x3)-cos(3*x4))-1;
f(3)=2*(cos(9*x1)-cos(9*x2)+cos(9*x3)-cos(9*x4))-1;
f(4)=2*(cos(15*x1)-cos(15*x2)+cos(15*x3)-cos(15*x4))-1;

3楼: Originally posted by 月只蓝 at 2013-10-21 15:35:54
function solvenonl_Eqs
clear all;clc
x0=;
x=fsolve(@Eqs,x0)
fval=Eqs(x)

function f=Eqs(x)
x1=x(1);
x2=x(2);
x3=x(3);
x4=x(4);
f(1)=2*(cos(x1)-cos(x2)+cos(x3)-cos(x4))-1-pi/4;
f(2)=2*(cos ...