Let X be metric space, and let g:X + R be uniformly continuous and h: R+R...
(TOPOLOGY) Prove the following using the defintion: Exercise 56. Let (M, d) be a metric space and let k be a positive real number. We have shown that the function dk defined by dx(x, y) = kd(x,y) is a metric on M. Let Me denote M with metric d and let M denote M with metric dk. 1. Let f: Md+Mk be defined by f(x) = r. Show that f is continuous. 2. Let g: Mx + Md be defined...
B2. (a) Let I denote the interval 0,1 and let C denote the space of continuous functions I-R. Define dsup(f,g)-sup |f(t)-g(t) and di(f.g)f (t)- g(t)ldt (f,g E C) tEI (i) Prove that dsup is a metric on C (ii) Prove that di is a metric on C. (You may use any standard properties of continuous functions and integrals, provided you make your reasoning clear.) 6 i) Let 1 denote the constant function on I with value 1. Give an explicit...
Question 3. (4 marks) Let C([a, b]; R) be the space of all continuous functions on [a, b], 0 <a<b with the metric || f – 9|| = maxasaso \f (x) – g(x)]. For each f e C([a, b]; R), define a map F(f) by F(f)(x) = x5 + Vx € (a,b]. (65 – a5) Prove that there is a unique fixed point of F in the space C([a, b]; R); i.e. there is a unique fe C([a,b); R) such...
- Let V be the vector space of continuous functions defined f : [0,1] → R and a : [0, 1] →R a positive continuous function. Let < f, g >a= Soa(x)f(x)g(x)dx. a) Prove that <, >a defines an inner product in V. b) For f,gE V let < f,g >= So f(x)g(x)dx. Prove that {xn} is a Cauchy sequence in the metric defined by <, >a if and only if it a Cauchy sequence in the metric defined by...
Let (X, d) be a compact metric space, and con- sider continuous functions fk : X → R, for k N, and f : X → R. Suppose that, for each the sequence (fe(x))ke N 1s a monotonic sequence which converges to (x). Show that r є X, k)kEN Converges to j uniformly. Let (X, d) be a compact metric space, and con- sider continuous functions fk : X → R, for k N, and f : X → R....
i) Does Lebesgue lemma hold true in the plane? Justify your answer! ii) Let (X, d1) be a compact metric space and (Y, d2) a metric space. Suppose that f : X → Y is continuous. Use Lebesgue lemma to show that for every > 0 there exists δ > 0 such that if d1(x, y) < δ then d2(f(x), f(y)) < , that is, f is uniformly continuous.
Let f : [0, 1] + R be uniformly continuous, so that for every e > 0, there exists 8 >0 such that |- y<f(x) - f(y)<for every x, y € (0,1). The graph of f is the set G = {(x, f(x)) : 2 € (0,1]}. Show that G, has measure zero
Let f : [0, 1] + R be uniformly continuous, so that for every e > 0, there exists 8 >0 such that 12 - y<88\f(x) - f(y)] <e for every x, y € (0,1). The graph of f is the set G= {(x, f(x)) : x € [0,1]}. Show that G has measure zero
Let f: [0,1]→R be uniformly continuous, so that for every >0, there exists δ >0 such that |x−y|< δ=⇒|f(x)−f(y)|< for every x,y∈[0,1].The graph of f is the set G f={(x,f(x)) :x∈[0,1]}.Show that G f has measure zero Let f : [0, 1] → R be uniformly continuous, so that for every e > 0, there exists 8 >0 such that 2- y<83|f() - f(y)< € for every 1, 9 € [0,1]. The graph of f is the set Gj =...
* Exercise 10. Let M be a (non-empty) compact metric space and f: M → M a continuous map such that for every ε > 0 there exists x E M such that d(f(x), z) < E. Show that there exists y M such that f()y Hint: consider the map g: MR defined by g(x)=d(f(x),z).] [8 marks]