3. For the following question, we only consider subsets of the set R of real numbers....
5. Let R denote the set of real numbers. Which of the following subsets of R xR can be written as Ax B for appropriate subsets A, B of R? In case of a positive answer, specify the sets A and B. (a) {(z,y)12z<3, 1<y< 2}, (b) {z,)2+y= 1), (c) {(z,y)|z= 2, y R), (d) {(z,y)|z,yS 0}, (e) {(z,y) z y is an integer).
We write R+ for the set of positive real numbers. For any positive real number e, we write (-6, 6) = {x a real number : -e < x <e}. Prove that the intersection of all such intervals is the set containing zero, n (-e, e) = {0} EER+
We write R+ for the set of positive real numbers. For any positive real number e, we write (-6, 6) = {x a real number : -e < x <e}. Prove that the intersection of all such intervals is the set containing zero, n (-e, e) = {0} EER+
Question 1: Let R be the set of real numbers and let 2R be the set of all subsets of the real numbers. Prove that 2 cannot be in one-to-one correspondence with R. Proof: Suppose 2 is in one-to-one correspondence with R. Then by definition of one- to-one correspondence there is a 1-to-1 and onto function B:R 2. Therefore, for each x in R, ?(x) is a function from R to {0, 1]. Moreover, since ? is onto, for every...
Consider the following functions, where I and J denote two subsets of the set R of real numbers. f: R→R x→1/√(x+1) f(I,J): I→J x→ f(x) (a) What is the domain of definition of f? (b Let y be an element of the codomain of f. Solve the equation f(x)=y in x. Note that you may have to consider different cases, depending on y. (c) What is the range of f? (d) Is f total, surjective, injective, bijective? (e) Find a...
This question is about "Real Analysis". Start with a set S c R and successively take its closure, the complement of its closure, the closure of that, and so on: S, cl(S), (cl(S))c,.... Do the same to Se. In total, how many distinct subsets of R can be produced this way? In particular decide whether each chain S, cl(S), consists of only finitely many sets. For example, if S = Q then we get Q, R, , , R, R,...
For the following question, consider only x > 0: CM R 3,1 - - - - - - - А/ x, \в { 0, x А/ 0,x \в 1,0 1. (5 points) Write this game in normal form. 2. (10 points) Consider the game we would have if we took out the strategy R. For each value of x find all the equilibria of this game. 3. (10 points) For what values of x is playing R the only rationalizable...
Let S be the set/vector space of all real numbers of the form a sart(2)+ b'pi, where a, b are any real numbers, where we add these numbers the usual way, and multiply by real number scalars the usual way. Find, another, simpler way, of describing this vector space
Let U be the set of all integers. Consider the following sets: S is the set of all even integers; T is the set of integers obtained by tripling any one integer and adding 1; V is the set of integers that are multiples of 2 and 3. a) Use set builder notation to describe S, T and V symbolically. b) Compute s n T, s n V and T V. Describe these sets using set builder notation
Need help, will rate, thanks. In class, we noticed something interesting: (-1) 2 4 This motivates a natural question: whether or not there exist other pairs of distinct real numbers x and y such that To avoid square-roots of negatives (complex numbers), we consider only pos- itive values of a and y. We use a graph to get us started: 0.5 0,5 Figure 1: The Solution Set for y. (Graphic created with Desmos) The line y = x isn't of...