给你个例子,自己参照这改吧!<BR>方程为1/a^5*(1/(exp(1/(a*x)-1))对a在1到3进行积分,x为未知数,整个方程等于1,求x <BR><BR><BR>% 解积分方程(被积函数中有未知数) <BR>syms a <BR>syms x positive <BR>ff=1/a^5/(exp(1/(a*x)-1)) <BR>ffx=int(ff,a,1,3); <BR>h1=subplot(211); <BR>ezplot(char(ffx)); <BR>hold on; <BR>plot(-[1,1],ylim,'r'); <BR>plot(-[3,3],ylim,'r'); <BR>plot(xlim,[0,0],'k'); <BR>h2=subplot(212) <BR>ezplot(char(ffx-1),[-1000,1000]); <BR>x1=-3;x2=-1; <BR>xx=(x1+x2)/2; <BR>yy=subs(ffx,xx); <BR>while abs(yy-1)<1e-8; <BR> xx=(x1+x2)/2; <BR> yy=subs(ffx,xx); <BR> if yy>0; <BR> x2=xx; <BR> else <BR> x1=xx; <BR> end <BR>end <BR>axes(h1) <BR>text(0,1,['roots: x=',num2str(xx)],'fontsize',14); <BR>plot(xx,1,'r*');plot(xx,1,'rs'); <BR> |