al=input(' al= '); for NN=1:19 N=NN+1 j=[0:1:N]; x=[cos(pi*j/N)]'; c=[2 ones(1,N-1) 2]; for k=1:N+1 if rem(k-1, 2)==0 b(k)=2/(1-(k-1)^2); else b(k)=0; end end for k=1:N+1 dd=0; for j=1:N+1 dd=dd+b(j)*cos((j-1)*(k-1)*pi/N)/c(j); end d(k)=2*dd/(N*c(k)); end for i=1:N+1 for j=1:N+1 if i==j A(i,j)=1+d(i)*exp(x(i)*x(i)); else A(i,j)=d(j)*exp(x(i)*x(j)); end end ss=x(i)+al; b(i)=exp(al*x(i))+(exp(ss)-exp(-ss))/ss; end u=A\b'; for i=1:N-1 u_true(i)=exp(al*x(i)); error(i)=abs(u(i)-u_true(i)); end xx(NN)=N; err(NN)=max(error); ss=max(error) end fprintf(1, '%10.0f %10.3e \n', [xx; err]);