i need question 2 parts a and b and the others problem are needed in it .here is program 4.2 in matlab:

function [ C,L ] = lagran(X,Y) %UNTITLED Summary of this function goes here % Detailed explanation goes here w=length(X); n=w-1; L=zeros(w,w); for k=1:n+1 V=1; for j=1:n+1 if k~=j V=conv(V,poly(X(j)))/(X(k)-X(j)); end end L(k,:)=V; end

C=Y'*L end

Program 4.2 (Newton Interpolation Polynomial). To construct and evaluate the k=0, 1, ,N: (21) | Newton polynomial of degree