In: Advanced Math
Let (sn) be a sequence that converges.
(a) Show that if sn ≥ a for all but finitely many n, then lim sn ≥ a.
(b) Show that if sn ≤ b for all but finitely many n, then lim sn ≤ b.
(c) Conclude that if all but finitely many sn belong to [a,b], then lim sn belongs to [a, b].
Here, first we prove the first part , further using this we prove the part (b), (c).
of a and b are disjoint.
Now part b:
Now part d:
Thus we are done!