Equivalence Classes for Relation on N

5b. Describe the equivalence classes for the following relations on N. x~y iif x mod 2 = y mod 2 and x mod 4 = y mod 4

Prove that R is reflexive.

8. Let R be a relation on a set S such that R is symmetric and transitive and for each x ε S there is an element y ε S such that x R y. Prove that R is an equivalence relation (i.e. prove that R is reflexive)

Analyzing an Algorithm

For the following algorithm find the number of times the addition operation (+) is executed during the running of the program. Answer the question by giving a formula in terms of n: for i := 1 to n do for j := 1 to i do x := x + f(x) od; x := x + g(x) od

Analyzing an Algorithm

For the following algorithm find the number of times the assignment statement (:=) is executed during the running of the program. Answer the question by giving a formula in terms of n: i := 1; while i < n + 1 do i := i + 2; for j := 1 to i do S od od

Permutations and Combinations

We wish to form a committee of 7 people chosen from 5 democrats, 4 republicans, and 6 independents. The committee will contain 2 democrats, 2 republicans, and 3 independents. In how many ways can we choose the committee?