using last inequality you can
also prove the result
Topology (c) Let P denote the vector subspace of C1O, 1] consisting of polynomial functions on [0,1. Let P be the closure of P in the sup norm of C[o, 1]. (i) Show that 5 is closed under pointwise mu...
Topology
(b) Let S denote the subset of co consisting of sequences with rational entries of which at most finitely many are nonzero. (i) Show that S is dense in co with the sup norm. [Hint: Show that for every r E co and every ε > 0, there exists y S such that llx-yI100 < ε.j (ii) Conclude that (co, ll . 114) is separable (only quote relevant results) (iii) Show that the closed unit ball in (a-II ·...
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...
vectors pure and applied
Exercise 11.3.1 Let Co(R) be the space of infinitely differentiable functions f R R. Show that CoCIR) is a vector space over R under pointwise addition and scalar multiplication. Show that the following definitions give linear functionals for C(R). Here a E R. (i)8af f (a). minus sign is introduced for consistency with more advanced work on the topic of 'distributions'.) f(x) dx. (iii) J f-
Exercise 11.3.1 Let Co(R) be the space of infinitely differentiable...
2. Consider the vector space C([0, 1]) consisting of all continuous functions f: [0,1]-R with the weighted inner product, (f.g)-f(x) g(x) x dr. (a) Let Po(z) = 1, Pi(z) = x-2, and P2(x) = x2-6r + 흡 Show that {Po, pi,r) are orthogonal with respect to this inner product b) Use Gram-Schmidt on f(x)3 to find a polynomial pa(r) which is orthogonal to each of po P1 P2 You may use your favorite web site or software to calculate the...
(7) In this problem let X denote the vector space C(0, 1) with the sup norm. (a) Given f e X, define d(f) = f2. : X → X is differentiable, and Prove that φ find φ'(f). (b) Given f e X, define 9(f) = J0 [f(t)]2dt. Prove that Ψ : X → R is differentiable. and find Ψ(f).
(7) In this problem let X denote the vector space C(0, 1) with the sup norm. (a) Given f e X,...
Topology
C O, 1 and be the supremum norm (a) Prove that (X || |) is a Banach space. You can assume that (X, | |) is a normed vector space (over R) |f|0supE0.1 \5(x)|.| 4. Let X C (b) Show that || |o0 that the parallelogram identity fails.] on X is not induced by any inner product. Hint: Check for all E[0, 1]. Show that {gn}n>1 (0, 1] BI= {gE X |9||<1} is a compact (c) For every 2...