function [U] =trial(x,n)

%
%  Calculates the first n trial functions on [-1,1]; 
%  we assume implicitly that the vector x is a row vector
%
%  U_1 = (1-x)/2
%  U_2 = (1+x)/2
%  U_n = \sqrt{(2n-3)/2}\int_{-1}^x L_{n-2}(t) dt     if n \ge 3
%
  U(1,:) = (1-x)/2;
  U(2,:) = (1+x)/2;
if n >2 
[P] = legtable(x,n);
  for i = 3:n
      ip=i-2;
        U(i,:) = sqrt((2*i-3)/2)*1/(2*ip+1)*(P(ip+2,:)-P(ip,:));
     end;
end;