nu=20;
de=conv([1 1],[1 1]);
w=logspace(-1,2);
set(0,'DefaultAxesFontName','times')
set(0,'DefaultAxesFontSize',16)
set(0,'DefaultTextFontName','times')
[mag,pha]=bode(nu,de,w);
loglog(w,mag,'r--',[.1 .999 1.001 100],[20 20 0.001 0],'r-')
xlabel('Frequency (rad/sec)')
ylabel('Magnitude')
legend('Approximation','Actual')
grid
