Complete Definition and 404 Threads

1. A’s rate of doing work is three times that of B. On a given day A and B work together for 4 hours; then B is called away and A finishes the rest of the job in 2 hours. How long would it take B to do the complete job alone? if I let x = B's rate of work and 3x...

Homework Statement This is not a homework problem, but a topic in a microeconomics book that I am unclear about. My book argues that the set X = {a, b, c, d} of preferences can be (i) transitive but (ii) incomplete. Is it possible for a similar set of preferences to be (i) complete but (ii)...

What is left if all matter and energy is removed from a particular region in space? For example, say I completely remove all of the matter and energy from a region of the air in front of me (also assuming no matter or energy moves in and out of this space once I do this), then what is left?

hello How to you rigorously express the orthonormality of a complete set of eigenvectors (|q\rangle)_q of the position operator given that these are necessarily generalized eigenvectors (elements of the distribution space of a rigged hilbert space)? The usual unformal condition \langle...

Homework Statement An EM wave is incident normally on a surface which absorbs all the electric field. Using maxwell equations, determine B-field on the other side. Homework Equations The Attempt at a Solution If all the E-field is absorbed, won't ET and Er = 0? Then none of...

Hey guys, I'm a complete beginner in electronics, and am looking for a beginner book to learn all about electronics. Can anyone give me some good reads?

Given a quadratic form: x^2 - 4xy + 6xz + 2xt + 4y^2 + 2yz + 4yt + 5z^2 - 6zt - t^2, find the symmetric matrix that defines this, row reduce this matrix into row echelon form, and use this upper triangle matrix to complete the square and write the quadratic form as the sum/difference of...

Homework Statement Let f:(X,A,μ)->[0,infinity] have a Lebesgue integral, meaning that the inf(upper lebesgue sum)=sup(lower lebesgue sum)=L for a finite L. Show that f is measurable with respect to the completion of the sigma algebra A with respect to μ. You may fix an integrable set E...

I know that a metric space is complete if every Cauchy sequence converges that will surely designate compact metric spaces as complete spaces . I need to see examples of metric spaces which are not complete. Thanks in advance !

Homework Statement I think my program is complete.. What happen to this line? u(i)=sin(pi*x(i)); ?? Homework Equations n=10; c1=0; c2=0; k= 0.0025; L=1; h=0.1; alpha=1; T=0.025; n=L/h;m=T/k; lambda =alpha*k/(h^2); z=0:h:L...

1. Homework Statement . Let ##(X,d)## be a complete metric space. Prove that if ##P \subset X## is perfect, then P is not countably infinite. 3. The Attempt at a Solution . Well, I couldn't think of a direct proof, I thought that in this case it may be easier to assume is countably infinite...

Homework Statement . Prove that if every closed ball in a metric space X is a complete subspace, then X is complete. The attempt at a solution. Let ##\{x_n\}## be a cauchy sequence in X. Then, for ##ε=1##, ##\exists## ##n_0 \in \mathbb N##: ##\forall## ##m≥n_0##,##n≥n_0##...

I want to understand the difference between Completely Randomized Design and Randomized Complete Block Design. Say for this example how we can categorize? An experiment is conducted to compare the starting salaries of male and female college graduates who find jobs. Pairs are formed by...

As far as I understand NP-complete problems are problems that are NP and have some other problem that is reducible to itself. Basically it is a set of problems that are NP-complete and if one is solved all are solved, right? What is the point of defining such set of problems? Also there might...

https://www.physicsforums.com/attachments/1163 well first want to see if i completed the tree diagram correctly text in the boxes are mine.

I've been watching a TV series recently called Person of Interest, it's really cool you should check it out. I'm curious though about people who somehow manage to completely wipe their identity and literally become a nobody and then acquire a new identity. I think legally the most thorough...

With my current understanding, the ordinary principle of Mathematical Induction is a method to prove, whether some statement ##P(x)## is true for all ##x## in ##\mathbb{Z}##, considering the truth of ##P(1)## and then the truth of ##P(k+1)## assuming ##P(k)## is true. For Complete Induction...

Homework Statement It is clear that a countable complete metric space must have an isolated point,moreover,the set of isolated points is dense.what example is there of a countable complete metric space with points that are not isolated? Homework Equations The Attempt at a Solution

Homework Statement I have to analyse the power output of a solar panel using a basic electrical engineering circuit analysis of a solar module if a complete row of solar cells in it is shadowed (For example, such shading might be caused by dust that slides down the surface of inclined panels.)...

Well I have no where else to look. I have tried various websites stores etc. I have looked into various sources sites extensively. And so far everything is just a source of aggravation. I can find all of the various parts but its over priced and takes to much searching to find parts. I just...

Hi, Let H = \{(x_n)_n \subseteq \mathbb{R} | \sum_{n=1}^{\infty} x_n < \infty \} and for $(x_n)_n \in H$ define $$\|(x_n)_n\|_H = \sup_{n} \left|\sum_{k=0}^{n} x_k \right|$$ Prove that $H$ is complete. Is $H$ a Hilbert space? What is the best way to prove $H$ is complete? To prove it's a...

2, 5, 14, 122, 365, ? The options are : a. 1029 b. 1094 c. 1059 d. 1000

Arrange the numbers: 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15 such that the summation of each two successive numbers is a complete square easy interesting question

Homework Statement Draw the best Lewis Dot Structures the following species: ClF4+Homework Equations none The Attempt at a Solution I calculated that there should be a total of 34 e- in the Lewis structure": 7 (1 chlorine atom) + 28 ( 7 from each of the four fluorine atoms) - 1(b/c the atom...

We might hear from one source or another that a famous scientist was always humiliated by his teacher when he was a student . We might hear about another who failed school or university but he became an inspiring figure after some years . So why do you think such things happen ? , is it because...

In the infinite square well, the stationary states solutions form a complete set, and therefore I can write a function such as ( f(x) = -x^2 + x ) as an infinite sum of them, But this function is, clearly, not a solution of S.E., although it's written as a sum of solutions. Why is it not a...

Homework Statement Consider the space of continuous functions in [0,1] (that is C([0,1]) over the complex numbers with the following scalar product: ##\langle f , g \rangle = \int _0 ^1 \overline{f(x)}g(x)dx##. Show that this space is not complete and therefore is not a Hilbert space. Hint:Find...

For a wave function describing the state of an isolated system in 1D, does a wave function describe a system completely?

Hi, I'm a high school student from Brazil who knows very little math, but I want to learn more (I've learned some stuff in school and forgot almost all of it).* Which books would you recommend? I've heard of Courant's What is Mathematics and of the Schaum's Outlines series. Are these...

In your opinion what is the best way to introduce completing the square, in fact I do not like the way sub and add the squared half of x coefficient, after making x^2 coefficient 1 saying it is complicated... Thanks

Homework Statement Could someone please help me do this problem?: “Write the complete solution as x_p plus any multiple of s in the nullspace: x + 3y + 3z = 1 2x + 6y + 9z = 5 –x – 3y + 3z = 5” The answer is x = x_p + x_n = {{-2},{0},{1}} + x_2 {{-3, 1, 0}}. Homework Equations Ax...

I can't find this anywhere on google. I'm looking for a complete list of functions and their inverses. Here's a partial list as an example *, / +, - e^x, ln(x) sin(), sin^-1() d/dx, ∫ etc.. Why isn't there a list of all of them? You would think that some mathematician would find joy in...

Introduction: A new cosmology based on the production of massless particles (in the early de Sitter phase) and ΛCDM particles (in the transition to a late time de Sitter stage) has been discussed. The same mechanism avoids the initial singularity, particle horizon and the late time coincidence...

"windows was unable to complete the format" Like myself, my PC is getting old! I have just noticed that it is not able to format any CD's and most DVD's. It certainly can not format any disk which has been erased. After 20 minutes of trying, it displays the message "windows was unable to...

Hello, forum! I am puzzling my way through some interpretation. In the famous EPR paper, the authors ask whether quantum mechanics is a 'complete' theory in the sense of whether or not the wave function completely describes the physical circumstances in question. EPR conclude that it is not...

Hello, I was wondering if it was possible (or advisable) to read Chapter 7 of Munkres (Complete Metric Spaces and Function Spaces) without having done Tietze Extension Theorem, the Imbeddings of Manifolds section, the entirety of Chapter 5 (Tychonoff Theorem) and the entirety of Chapter 6...

Ok, so I know that the laws of physics say reaching absolute zero temperature is impossible, but suppose we took a box that was perfectly insulated in completely empy space, and I took all the particles out of it to create a vacuum. Now, since there are no particles in the box, then wouldn't...

Homework Statement There was a question on my exam a few days ago. Using Lagrange to find the max/min on a region. We only had to answer a certain amount of questions and I never got to this one. I'm working on it now though out of curiosity. R = { (x,y) | x2 + xy + y2 ≤ 3 } f(x,y) =...

Homework Statement Assume a relation P that is asymmetric on a set X that is not empty. Define the binary relation R on X by xRy iff y P x is false. Prove that R is complete Homework Equations Asymmetry: xRy \rightarrow \neg (yRx) Now, I think I got a proof, but I am not sure...

I'm taking PoMA-Rudin, do I have to complete all the exercises after every chapter to be regarded as understanding the material ? Does all the tools for solving the exercises lie in the material? Because I feel many problems require more than the textbook. Thanks.

Homework Statement A source of light emits a train of waves lasting 0.04 μs. The light has a wavelength of 600nm and the speed of light is 3×108ms-1. How many complete waves are sent out? a)2.0×107 b)4.5×107 c)2.0×1010 d)4.5×1013 Homework Equations f=v/wavelength (sorry, I couldn't...

Let's say I'm looking at the infinite square well. Typically, given some arbitrary initial (normalized) wavefunction, we can decompose it into a linear combination of components of the complete set (on the interval [-a,a] or whatever) of sin's and cos's. Then, if you measure something like the...

Homework Statement Let X and Y be metric spaces such that X is complete. Show that if {fα(x) : α ∈ A} is a bounded subset of Y for each x ∈ X, then there exists a nonempty open subset U of X such that {fα(x) : α ∈ A, x ∈ U} is a bounded subset of Y. Homework Equations Definition of...

"All Lp spaces, (except where p=∞) fail to be complete under the Reimann integral"? I am trying to learn about the Lebesgue integral and Lebesgue measurability. None of my textbooks really cover it from the basics, but I found this document online which seems to be pretty through in...

Homework Statement Hi everyone, I am just wondering how you would solve this question.. 2. Elevator Problem (Practice on Segmented Motion) A hotel elevator ascends 200 m with maximum speed of 5 m/s. Its acceleration and deceleration both have a magnitude of 1.0 m/s How long does...

I'm wondering if the list of particles in the SM is both complete and unique? Or could we find other particles and interactions that could also be included in the SM? Phyisicists sometimes invent fields and particles to account for Dark matter and inflation, etc. But that introduces particles...

Well, my move to Tucson is completed! 1100 miles, 20 hours, most of which was across Texas! (Shreveport, LA to Tucson, AZ) Glad to be out here in Tucson finally. Already sent in my application to join the local astronomy organization, and I can't wait to go to some of the observatories around...

hello! is there a complete list of mathematical notations? thanks!

hello! can you post your bookmarks about: - book repositories - journal repositories - database repositories - electronic material repositories etc for example, when you are looking for all possible books about a specific subject, you just search at amazon? or what else? thanks!

I used to test orthogonality by using the definition MT = M-1, which means I always calculated the inverse of the matrices. However, isn't it true that if M is orthogonal, then MMT = I? If we multiply both side by M-1, we get MT = M-1. Can I use this to proof the orthogonality of a matrix...