% Example 10.2a (Physics 330)

close all;
N=1000;
a=0;
b=5;
dx=(b-a)/N;
x=.5*dx:dx:b-.5*dx;  % build an x array of centered values
f=cos(x);  % load the function

% do the approximate integral

s=sum(f)*dx

% compare with the exact answer, which is sin(5)

err=s-sin(5)