Question
Asked by:
falcon6
falcon6
Rating : No Rating
Questions Asked: 61
Tutorials Posted: 0
 

$3.00 counting principles; probability 8-37

Q:
In this exercise we study the connection between sets and combinations.
a. Given a set with n elements, what is the number of subsets of size 0? of size 1? of size 2? of size n?
b. Using your answer from part a, give an expression for the total number of subsets of a set with n elements.
c. Using your answer from part b and a result from Chapter 7, explain why the following equation must be true:
(n) + (n) + (n) + ... + (n) = 2(to the n power)
(0) (1) (2) (2)

d. verify the equation in part c for n=4 and n=5

ANSWERS:
a. (n), or 1; (n), or n; (n); (n), or 1
(0) (1) (2) (n)

b. (n)+(n)+(n)+ ... +(n)
(0) (1) (2) (n)
 


   
   
   
   
 
Available Tutorials to this Question
Posted by:
math_tutor
math_tutor
Rating (231): A-
Questions Asked: 0
Tutorials Posted: 842, earned $4,925.19
 

$3.00 A+ solution step by step

  • This tutorial hasn't been purchased yet.
  • Posted on May 14, 2009 at 1:30:10PM
A:
Preview: ... teps explai ...

The full tutorial is about 7 words long plus attachments.

Attachments:
subsets.docx (77K) (Preview)
Posted by:
b_h
b_h
Rating (671): A+
Questions Asked: 0
Tutorials Posted: 1188, earned $24,653.40
 

$3.00 Counting Help

  • This tutorial was purchased 1 time and rated A+ by students like you.
  • Posted on May 14, 2009 at 1:42:11PM
A:
Preview: ... se 0).<br><br>There are exactly n subsets of size 1. We can form them by choosing 1 element from the n to be in the subset. We can do this is n ways. We also call this (n choose 1)<br><br>To form a two element subset, we choose the first element in n ways. Then we choose the second element from the remaining (n-1) elements in (n-1) ways for a total of n*(n-1). But this over-counts since order doesn't matter (we could choose ...

The full tutorial is about 406 words long .
   
Join Now or Log In
Get Tutoring
Get Paid
Academic Honesty