p.77 - 5c   |(3n+1)/(2n+5) - 3/2| = |(3n + 7.5 - 6.5)/(2n+5) - 3/2| =
            |(-6.5)/(2n+5)| LT 8/2n = 4/n.  If K(epsilon) = 4/(epsilon),
            |(3n+1)/(2n+5) - 3/2| LT 4/(4/(epsilon)) = epsilon if n GT
            K(epsilon) as per the definition.

       9    Let epsilon = x/2.  if n GT K(epsilon), x_n GT x-(x/2), hence GT 0.