13. Consider functions f: {1,2,3,4} {1, 2, 3, 4, 5, 6}. → a. How many functions are there total? b. How many functions are injective? c. How many of the injective functions are increasing? To be increasing means that if a < b then f(a) f(b), or in other words, the outputs get larger as the inputs get larger. 14. We have seen that the formula for P(n, k) is n! (n-k)! Your task here is to explain why this is the right formula. a. Suppose you have 12 chips, each a different color. How many different stacks of 5 chips can you make? Explain your answer and why it is the same as using the formula for P(12,5). b. Using the scenario of the 12 chips again, what does 12! count? What does 7! count? Explain. c. Explain why it makes sense to divide 12! by 7! when computing P(12,5) (in terms of the chips). d. Does your explanation work for numbers other than 12 and 5? Explain the formula P(n, k) = using the variables n and k. n! (n-k)!

Advanced Engineering Mathematics
10th Edition
ISBN:9780470458365
Author:Erwin Kreyszig
Publisher:Erwin Kreyszig
Chapter2: Second-order Linear Odes
Section: Chapter Questions
Problem 1RQ
icon
Related questions
Question
Combinatorics. Show solution to your answer.
13. Consider functions f: {1,2,3,4} {1, 2, 3, 4, 5, 6}.
a. How many functions are there total?
b. How many functions are injective?
c. How many of the injective functions are increasing? To be increasing
means that if a < b then f(a) < f(b), or in other words, the outputs get
larger as the inputs get larger.
n!
14. We have seen that the formula for P(n, k) is
. Your task here is to
(n - k)!
explain why this is the right formula.
a. Suppose you have 12 chips, each a different color. How many different
stacks of 5 chips can you make? Explain your answer and why it is the
same as using the formula for P(12,5).
b. Using the scenario of the 12 chips again, what does 12! count? What does
7! count? Explain.
c. Explain why it makes sense to divide 12! by 7! when computing P(12,5) (in
terms of the chips).
d. Does your explanation work for numbers other than 12 and 5? Explain the
formula P(n, k)
n!
=
(k) using the variables n and k.
(n-k)!
Transcribed Image Text:13. Consider functions f: {1,2,3,4} {1, 2, 3, 4, 5, 6}. a. How many functions are there total? b. How many functions are injective? c. How many of the injective functions are increasing? To be increasing means that if a < b then f(a) < f(b), or in other words, the outputs get larger as the inputs get larger. n! 14. We have seen that the formula for P(n, k) is . Your task here is to (n - k)! explain why this is the right formula. a. Suppose you have 12 chips, each a different color. How many different stacks of 5 chips can you make? Explain your answer and why it is the same as using the formula for P(12,5). b. Using the scenario of the 12 chips again, what does 12! count? What does 7! count? Explain. c. Explain why it makes sense to divide 12! by 7! when computing P(12,5) (in terms of the chips). d. Does your explanation work for numbers other than 12 and 5? Explain the formula P(n, k) n! = (k) using the variables n and k. (n-k)!
7. An anagram of a word is just a rearrangement of its letters. How many
different anagrams of "uncopyrightable" are there? (This happens to be the
longest common English word without any repeated letters.)
8. How many anagrams are there of the word "assesses" that start with the
letter "a"?
Solution
9. How many anagrams are there of "anagram"?
10. On a business retreat, your company of 20 businessmen and
businesswomen go golfing.
a. You need to divide up into foursomes (groups of 4 people): a first
foursome, a second foursome, and so on. How many ways can you do
this?
b. After all your hard work, you realize that in fact, you want each foursome
to include one of the five Board members. How many ways can you do
this?
Solution
11. How many different seating arrangements are possible for King Arthur and
his 9 knights around their round table?
Solution
12. Consider sets A and B with |A| = 10 and |B| = 17.
a. How many functions f: A → B are there?
b. How many functions f: AB are injective?
Transcribed Image Text:7. An anagram of a word is just a rearrangement of its letters. How many different anagrams of "uncopyrightable" are there? (This happens to be the longest common English word without any repeated letters.) 8. How many anagrams are there of the word "assesses" that start with the letter "a"? Solution 9. How many anagrams are there of "anagram"? 10. On a business retreat, your company of 20 businessmen and businesswomen go golfing. a. You need to divide up into foursomes (groups of 4 people): a first foursome, a second foursome, and so on. How many ways can you do this? b. After all your hard work, you realize that in fact, you want each foursome to include one of the five Board members. How many ways can you do this? Solution 11. How many different seating arrangements are possible for King Arthur and his 9 knights around their round table? Solution 12. Consider sets A and B with |A| = 10 and |B| = 17. a. How many functions f: A → B are there? b. How many functions f: AB are injective?
Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 2 steps

Blurred answer
Recommended textbooks for you
Advanced Engineering Mathematics
Advanced Engineering Mathematics
Advanced Math
ISBN:
9780470458365
Author:
Erwin Kreyszig
Publisher:
Wiley, John & Sons, Incorporated
Numerical Methods for Engineers
Numerical Methods for Engineers
Advanced Math
ISBN:
9780073397924
Author:
Steven C. Chapra Dr., Raymond P. Canale
Publisher:
McGraw-Hill Education
Introductory Mathematics for Engineering Applicat…
Introductory Mathematics for Engineering Applicat…
Advanced Math
ISBN:
9781118141809
Author:
Nathan Klingbeil
Publisher:
WILEY
Mathematics For Machine Technology
Mathematics For Machine Technology
Advanced Math
ISBN:
9781337798310
Author:
Peterson, John.
Publisher:
Cengage Learning,
Basic Technical Mathematics
Basic Technical Mathematics
Advanced Math
ISBN:
9780134437705
Author:
Washington
Publisher:
PEARSON
Topology
Topology
Advanced Math
ISBN:
9780134689517
Author:
Munkres, James R.
Publisher:
Pearson,