Chapter 11.4
#15
See link below:
-Jose Betance
For those of you who would like a reminder about the questions from Quiz #5 and #6…
Quiz #5 (Rosen 11.2 #2)
Build a binary search tree for the words oenology, phrenology, campanology, ornithology, ichthyology, limnology, alchemy and astrology using alphabetical order.
Quiz #6 (Rosen 11.5 #2 and #6)
(a) Use Prim’s algorithm to find a minimum spanning tree for the given weighted graph.
(b) Use Prim’s algorithm to find a minimum spanning tree for the given weighted graph.
Exercise: Complete parts (b) and (c) below for your team.
Team parentheses:
Let be the number of ways of parenthesizing a product of
numbers.
Team binary rooted trees:
Let be the number of full, binary, rooted trees with
leaves.
Team triangulated polygons:
Let be the number of ways of triangulating a polygon with
sides.
(b) Find a recursive formula for . (That is, find a formula for
in terms of
.)
(c) Use your formula from (b) to determine and
.
Exercise: Complete part (a) below for your team.
Team parentheses:
Let be the number of ways of parenthesizing a product of
numbers.
Team binary rooted trees:
Let be the number of full, binary, rooted trees with
leaves.
Team triangulated polygons:
Let be the number of ways of triangulating a polygon with
sides.
(a) Find for
.
In the following exercise, you will be defining sequences of numbers recursively. That means that a number in the sequence is defined in terms of the numbers coming before it.
Exercise 1: Complete parts (a), (b), and (c) below for your team.
Team rabbit:
One pair of very young rabbits (one male and one female) is dropped on a deserted island. After they are two months old, they give birth to one new pair of rabbits (one male and one female) per month. Let be the number of rabbits living on the island after
months.
Team bitstring:
Let be the number of bitstrings of length
that do not have two consecutive 0s.
(a) Find for
.
(b) Find a formula for in terms of the
for
. (This is called a recurrence relation.)
(c) Use your formula from (b) to find .
Edit: We saw in class that both teams’ sequences of numbers were equal. This sequence is known as the Fibbonacci sequence. This sequence pops up all over mathematics, not just in the two examples above. You can read more about it here.