QUESTION 10 The equality relationon any set S is: A total ordering and a function with an inverse. An equivalence relation and also function with an inverse. A function with an inverse, and an equiva...
2. Let S 11,2,3,4,5, 6, 7,8,91 and let T 12,4,6,8. Let R be the relation on P (S) detined by for all X, Y E P (s), (X, Y) E R if and only if IX-T] = IY-T]. (a) Prove that R is an equivalence relation. (b) How many equivalence classes are there? Explain. (c) How mauy elements of [ø], the equivalence class of ø, are there? Explain (d) How many elements of [f1,2,3, 4)], the equivalence class of (1,2,3,...
I. Let each of R, S, and T be binary relations on N2 as defined here: R-[<m, n EN nis the smallest prime number greater than or equal to m] S -[< m, n> EN* nis the greatest prime number less than or equal to m] (a) Which (if any) of these binary relations is a (unary) function? (b) Which (if any) of these binary relations is an injection? (c) Which (if any) of these binary relations is a surjection?...
probelms 9.1
9 Modular arithmetic Definition 9.1 Let S be a set. A relation R = R(,y) on S is a statement about pairs (x,y) of elements of S. For r,y ES, I is related to y notation: Ry) if R(x,y) is true. A relation Ris: Reflexive if for any I ES, R. Symmetric if for any ry ES, Ry implies y Rr. Transitive if for any r.y.ES, Ry and yRimply R. An equivalence relation is a reflexive, symmetric and...
2. (5pt) Consider the following binary relations. In each case prove the relation in question is an equivalence relation and describe, in geometric terms, what the equivalence classes are. (a) Si is a binary relation on R2 x R2 defined by z+ly-+ 1 r,y). (,y) e S Recall that R =R x R. (b) Sa is a binary relation on R defined by 1-ye2 r,y) e S
a. A function f: A B is called injective or one-to-one if whenever f (x) f(u) for some z, y A then y. Which of the following functions are injective? In r-y. That is Vr,y E A f()-f(u) each case explain why or why not i. f:Z Z given by f(z) 3 7 ii. f which maps a QUT student number to the last name of the student with that student number. b. Suppose that we have some finite set...
2. A binary string s a finite sequence u = ala2 . . . an, where each ai įs either 0 or 1. In this case n is the length of the string v. The strings ai,aia2,...,ai...an-1,aan are all prefixes of v. On the set X of all binary strings consider the relations Ri and R2 defined as follows R, = {(u, u) | w and u have the same length } {(w, u) | w is a prefix of...
Question 8
Let R be relation on a set A. 1. When is R said to be an equivalence relation? Give a precise definition, using appropriate quantifiers etc. 2. When is R said to be an partial order? Give a precise definition, using appropriate quantifiers etc (You don't need to redefine things that you defined in the previous part... you may simply mention them to save time.) 3. On Z, define a relation: a D biff a - b is...
2 Functions a. A function f : A-B is called injective or one-to-one if whenever f(x)-f(y) for some x, y E A then x = y. That is Vz, y A f(x) = f(y) → x = y. Which of the following functions are injective? In each case explain why or why not i. f:Z-Z given by f() 3r +7 (1 mark ii. f which maps a QUT student number to the last name of the student with that student...
4. Let S be the set of continuous function f: [0;1) ! R. Let R be the relation defined on S by (f; g) 2 Rif(x) is O(g(x)). (a) Is R reflexive? (b) Is R antisymmetric? (c) is R symmetric? (d) is R transitive? Explain your answer in details. Use the definition of big-O to justify your answer if you think R has a certain property or give a counter example if you think R does not have a certain...
Question 11 Let's define an equivalence relation R on the set of integers by aRb if and only if 5|3a + 7b What is the cardinality of the partition induced by R? Not yet answered Points out of 1.00 P Flag question Select one: a. 1 O b.4 O C. 5 d. 2 O e. 7 O f. infinite