Determine if the sequence is (a) bounded above, (b) bounded below, and (c) bounded or unbounded.
an = (-1)n2n
The terms of this sequence alternate between positive and negative, getting farther from 0 with no bounds anywhere in sight.
a) No, this sequence is not bounded above.
b) No, this sequence is not bounded below.
c) This sequence is unbounded. It has no upper or lower bound.