while 1
a=input('Enter the limit\n');
x=0:0.05:a;
clear a;
y=sin(2*x);
z=2*cos(2*x);
plot(x,y,'k-',x,z,'b--');
legend('sin(2\omega)','2Cos(2\omega)');
xlabel('x');
ylabel('sin(2\omega)-d/dx');
title('Df');
grid on;
end

%press ctrl+c to end this program