fprintf('Percent Error  xi+1       n\n')
q6_A('cos(x)',pi/6,pi/6,.1);
q6_A('sin(x)',0,pi/6,10^(-6));
q6_A('log(x)',0.5,.2,.01);
q6_A('x^6-3*x^3+x^2-14',-1,.1,.01);
q6_A('x^6-3*x^3+x^2-14',-1,.1,10^(-12));