function  prob40(  )
%UNTITLED5
close all
x = linspace(-100.01,.99,1020);
f1 = .5*abs(1-(1-x).^(-1/2));
f2 = (5.*(1-x) + 2*sqrt(1-x))./abs(x);
plot(x,f1,'-r')
figure
plot(x,f2,'-b')
end

