function g = hamlap (x)
    %
    %g = log (20-x);                             %y = exp(x) + x - 20                                     voi nam ngoai (19;21)
    %g = log (20+x);                              %y = exp(x) - x - 20                                    voi nghiem x>0 nam ngoai (-21;-19)
    %g = exp (x) -20;                            %y = exp(x) - x - 20                                     voi nghiem x< 0
    %g = log (x + 20);                           %y = exp(x) - x - 20                                     voi nghiem x< 0
    
    %g = - sin(x) +.01 ;                         % y = x + sin(x) + 1
    %g = (-log(x) +10).^(1/3);                   %y = log(x) + x^3 - 10; 
    %g = exp(x) - x + x^3 + x^5 + 0.1 ;          % y = x^5 + x^3 - x + 0.1
    %g = log(x) - x + x^3 + x^5 + 1/10 ;         % y = x^5 + x^3 - x + 0.1
    %g = x^5 + x^3 + 0.1                         % y = x^5 + x^3 - x + 0.1                                voi x~0
    %g = exp(log(x^5) + x^5 + x^3 + 0.1))/5 ;      y = x^5 + x^3 - x + 0.1                                voi x~-1
    %g = exp(log(x^5) - x^5 - x^3 - 0.1))/5 ;      y = x^5 + x^3 - x + 0.1                                voi x~-1
    
   %y = exp(x) + x^2 - 10                         %g= (-cos(x)-5)/5;                     g = (2-log(x))/5;
=======
    %g = (2-log(x))/5;
    g = ( -9 - log(x.^2)).^(1/3)/2.^(1/3) ;       % y = log(x.^2) + 2*x.^3 + 9; % trong khoang (-2; -1)
>>>>>>> 80f1f15b8f9b51ea852b90b0d34bef797d8a7da5
