What is the number of subsets of a set with n elements, containing a given element?
the textbook answer is 2^(n-1), why do we subtract the given element?
What is the number of subsets of a set with n elements, containing a given element?...
Let P(n) be the proposition that a set with n elements has 2" subsets. What would the basis step to prove this proposition PO) is true, because a set with zero elements, the empty set, has exactly 2° = 1 subset, namely, itself. 01 Ploi 2. This is not possible to prove this proposition. 3. po 3p(1) is true, we need to show first what happens a set with 1 element. Because, we can't do P(O), that is not allowed....
4. Ranking/Unranking Subsets. Let A be a set of n elements and set Sk(A) be the collection of all k-element subsets of A. Recall that |Sk(A)I - (a.) (8 points) Describe a ranking algorithm to rank a k-element subset of an n-element set. (b.) (8 points) Describe an unranking algorithm to unrank an integer 0 < s< [into a ithm to unrank an integer 0 S s <C) k-element subset of an n-element set. (c.) (10 points) As examples, let...
Find the number of subsets of each possible size for a set containing four elements Use the definition of the determinant to show that det(A) umciy thummy ice-cream). 2. (20 pts 6 pts +6 pts + 7 pts) Convert the following sentences to Conjunctive Normal Form (CNF): (c) (PA Q)P Q)
Prove that all sets with n elements have 2n subsets. Countthe empty set ∅ and the whole set as subsets.
Use induction to prove that every set of n elements has 2n distinct subsets, for all n ? 0. Hint for the inductive case: fix some element of the set and consider whether it belongs to the subset or not. In either case, reduce to the inductive hypothesis.
7. Let A, , An be non-empty subsets of a finite set Ω. If 1 k n and Ek is the set of elements in Ω which belong to at least k of the Ai's show that Pal i-1 7. Let A, , An be non-empty subsets of a finite set Ω. If 1 k n and Ek is the set of elements in Ω which belong to at least k of the Ai's show that Pal i-1
5. Binomial Coefficients (a) How many subsets with at least 5 elements does a set with 8 elements have? n+3 (b). Find the coefficient of z" in (3-2)+ (c). How many ways are there to walk down from the top of Pascal's Triangle and end somewhere on the number 20? 5. Binomial Coefficients (a) How many subsets with at least 5 elements does a set with 8 elements have? n+3 (b). Find the coefficient of z" in (3-2)+ (c). How...
,n2} with ISI = n. 4. Let n be a positive integer with n > 20, and let S {1, 2, -I with a) Show that S possesses two dilferent 3-element subsets, the sums of whose elements are equal. (b) Show that S possesses two disjoint subsets, the sums of whose elements are equal ,n2} with ISI = n. 4. Let n be a positive integer with n > 20, and let S {1, 2, -I with a) Show that...
2. Given the set S-ta,b,c,d,e,f,g,h) a) How many subsets does S have? b) How many subsets have exactly 5 elements? c) A subset is randomly chosen for the collection of all possible a) b) c) subsets. What is the probability that it contains exactly 3 elements? d) A subset is chosen at random from all the subsets. d) What is the probability that it contains the element a?
1. Let S and T be subsets of the universal set U. Use the Venn diagram on the right and the given data below to determine the number of elements in each basic region. n(U)=25 n(S)=13 n(T)=14 n(SUT)=19 Region I contains _____ elements Region II contains _____ elements Region III contains _____ elements Region IV contains _____ elements ______________________________________________________________________________________________________ 2. Let R, S, and T be subsets of the universal set U. Use the Venn diagram on the right and...