@Carl Love Thank you so much!.

Newton:=proc(f,p0,TOL,N)  

 local i,p;   i:=1;

 while i<= N do      

     p:=p0-(f(p0))/(diff(f(p0),x));    

     if abs(p-p0)<TOL then             return p;     else i:=i+1;            p0:=p; end if;  

end do;

printf("The method failed after N iterations,N=%d",N);  end proc:
But:

f:=x->exp(x)-x-2;
p0 := 2;
TOL := 10^(-5);
N := 50;
Newton(f, p0, TOL, N);

Maple noticed "error"

@vv Sorry, all of you. I don't know how to create a matrix which have det=2. I don't understand

@acer Thank you very much

@tomleslie How thoughtful.Thank you very much!

@Thomas Richard Yes. That is Cholesky decomposition. You see, Ly=b, Transpose(L)x=y, Maple notice "error". I don't understand. Can you explaint it to me? Thank you so much!  ll.mw

@tomleslie Thank you very much! . I have written it. Can you help me read a program which I have written? I really appreciate it! Sorry you, my English is not so good!

Download ll.mw

@acer Thank you very much!

@tomleslie Thank you so much!

@Carl Love Thanks for your help! 

@Carl Love Thank you so much! :D 

@tomleslie 

Thank you so much! 

nevilee:=proc(X,Y,x)  

local  i,j, n, Q;  

n:=nops(X)-1;  

Q:=array(0..n,0..n,[]);  

P:=array(0..n,[]);  j:=0;  

for i to n+1 do      

Q[i-1, j]:=op(i,Y);      

P[i-1]:=op(i,X);  od;

 for i to n do  

    for j to i do    

   Q[i,j]:=((x-X[i-j))*Q[i,j-1]-(x-X[i])*Q[i-1,j-1])/(X[i]-X[i-j]);        od;  od;

 for i from 0 to n do      

    printf("%f",P[i]);  

for j from 0 to i do    

    printf("%f",Q[i,j]);  od;  

printf("\\n");  od;  end proc:

I writed but I don't know errors

@Preben Alsholm Thank you so much

@tomleslie Thank you so much!

@Carl Love  Thank you very much! :D