Writing Definition and 712 Threads

Hi When the dielectric function of a system is time-invariant, solutions of Maxwell's Equations are separable and they are usually written as (I only write the E-field) E(r, t) = E(r) \exp(-i\omega t) Now, in my book they write an optical field as E(t) = E_0\exp(-i\omega t) +...

How would I write 1 + n + n(n - 1) + n(n - 1)(n - 2) + ･･･ + n! in sigma notation? If it's possible.

Is there a good free/cheap editor for easily/rapidly writing equations? I need to write 3+ papers in the next 2 months and they all have a lot of matrices and equations with indices and all those things that take forever to enter in using MS Word. I hate spending hours on entering that stuff...

I'd preferably want something that could replace scratch paper. The iPad's stylus is far too thick for comfortably writing up math equations. Thanks!

http://nakedsecurity.sophos.com/2012/01/24/canadian-resident-sentenced-to-death-for-writing-a-computer-program/ I just can't believe this. If anyone wanted proof that Iran's leadership is not in any way civilized, this is it. I feel that something should be done, but I just am not sure what yet.

Homework Statement For the following remote controlled toy cars, write vector equations for their positions in the form r=a+tb (a=initial position vector, b=velocity vector, r= position vector at any time t sec, distances in cm) d. the car is traveling at 15cm/s in the direction 3i+4j...

Bonnet’s recursion formula for Legendre polynomials is P(n,x)=1 for n=0 P(n,x)=x for n=1 and P(n,x)= (2n-1)/n*x*P(n-1,x)-(n-1)/n*P(n-2,x) I tried to write recursive function in C to calculate the value of polynomial for a given n and x float legpol(int n, float x) {...

Homework Statement A new car that costs $30,000 has a book value of $18,000 after 2 years. a) Find a linear model that represents the value 'V' of the care after 'x' years b) Find an exponential model of V= ab^(x) that represents the value 'V' of the car after 'x' years...

I'm writing a report and I'm having trouble coming with the right words to describe a procedure. Is there a better way to say "Before wiring PB2 (pushbutton) to the relay, refer to the wiring label on the relay to find the relay socket terminals function." ? What I want to say is learn where...

Homework Statement Write f(x) = |x2-x-12| as a piecewise function. Homework Equations The Attempt at a Solution -x2+x+12 where x>1/2 x2-x-12 where x\geq0 According to the answer book the answers are -x2+x+12 where -3<x<4 x2-x-12 where x\geq4 2x2-5x-3, x\leq1/2 I am...

Please forgive me if this fell into the wrong forum. I thought this would be the right place to ask. 500 million years have past since humanity came in control of a device that could send ships at great speeds across the universe, from the edge of one galaxy to the edge of another in weeks...

What is your favorite writing tool and why? Do you prefer pen or pencil for doing math/physics and why? What about for normal writing? For awhile I've been using a Rotring 600 silver drafting pencil that was passed down to me, but I'm still not sure whether I prefer pencil or pen. I have...

Homework Statement Given the following defined transformation T(a + bt+ct^{2}) = (a+c) - (c+b)t + (a+b+c)t^{2} find the matrix with respect to the standard basis From my understanding, the standard basis for a 3 element vector would be (0,0,1)^{T} (0,1,0)^{T}...

Many journals encourage authors to use their special latex packages (e.g., revtex4-1 for physical review a,b etc) while sending an article for peer-review process. I am not sure if this is compulsory or optional. Will an article be rejected if it is written not using the special latex packages...

Hello, In the notation adopted by Peskin and Schroeder, the single particle state is \left|\boldsymbol{p}_1, s_1\right\rangle = \sqrt{2 E_{p}} {a_{p_1}^{s_1}}^{\dagger}\left|0\right\rangle How does one write down \left\langle r|\boldsymbol{p}_1, s_1\right\rangle = \sqrt{2 E_{p}} \left\langle...

Homework Statement given: Vn+1=Vn*cos(pi/2^(n+2)) Homework Equations Write a sequence Vn in terms of n The Attempt at a Solution we substitute n with n-1 and we get: V(n-1)+1= Vn-1*cos(pi/2^(n-1+2)) Vn=Vn-1*cos(pi/2^(n+1) Is this correct?

I am new to quantum physics. My question is how to write the Hamiltonian in dirac notation for 3 different states say a , b , c having same energy. I started with Eigenvaluee problem H|Psi> = E|psi> H = ? for state a? SO it means that indvdually H= E (|a><a|) for state a and for all three...

I want to learn how to write professional looking letters so I have to learn how to use punctuation and stuff properly. As silly as it seems, I still don't know when and where to use commas. I used to not know how to use them at all but someone advised me to sound out the sentence in my head and...

I hate having to sign my name! Why? I don't have the ability to consistently sign something in a nearly identical way. Right now I'm signing the publication copy of my thesis and I've printed up 6 copies of the page that I need to sign my name on just because I know I'm not going to be satisfied...

Homework Statement On http://www.chem.arizona.edu/~salzmanr/480b/statt02/statt02.html they're going from a three-fold summation to a single summation (cubed) (equation 58-59), something like this: \sum_{n_x} \sum_{n_y} \sum_{n_z} e^{-a\left(n_x^2 + n_y^2 + n_z^2\right)} = \left( \sum_n...

I am comparing LP's and SDP's and have come across a lot of papers where they show all of the differences, but I am trying to put an lp is sdp form. The reason being I have solved an advanced sdp using an online solver and can solve basic/advanced lps on my pc, but I now want to take a lp and...

Did anyone write a program before for Newton Raphson method on MATLAB. I need to try the program to solve 2 equations: cox=x^3 and x^4-0.5(x^3)+3(x^2)-x+3=0 Please Help me in this manner ASAP. AND THANK YOU

I have four essays to write for my internship each of a maximum of 350-400 words. I just wrote my first essay and I feel relatively content with it. Though I can't help but doubt my work.. I wrote it rather unconventionally you can say. Instead of being very formal, I used more of a...

I suppose this has to go under homework, so here it goes: I'm in Calc III and we won't have enough time to cover the last chapter in the textbook about Stokes theorem, Green's theorem, and the divergence theorem, so instead the teacher wants a 7-page paper on something from that chapter. She...

Homework Statement A region R is given. (ill just tell you that it is a triangle, given by lines x = -2, y = 2, and y = x). Decide whether to use polar coordinates or rectangular coordinates and write \int\int f(x,y)dA as an iterated intergal, where f is an arbitrary continuous function...

Homework Statement I'm having some issues coming up with a proof for |- (Box(P) ^ Box(Q)) -> Box(P ^ Q). Box is the unary operator for "necessary for". Homework Equations Axiom 1 A -> (B -> A) Axiom 2 (A -> (B -> C)) -> ((A->B) -> (A -> C)) Axiom 3 (~a -> B) -> ((~A -> ~B) -> A)...

Hello, I understand that this question may seem rather obvious for some. Nonetheless, it is something that seems to have thrown me off a number of times. When writing chemical equations involving acidic or basic solutions, I know that the acid on the reactant side is written with the state...

Folks, I find it very tedious writing using latex symbols on this forum, i.e. I continually have to click ‘preview’ to see that the equations turn out ok before submitting. Is there some compiler I can use that generates the math independently of this forum then I could copy and paste onto...

I don't know how often you get questions like this here, if ever, but I was hoping you could help me solve a problem I have come across in writing a story. It is not exactly Hard Sci Fi, but it is definitely not soft science fiction, and I want to get the physics at least mostly right. Here it...

Please Help! I'm writing a novel involving worm holes and asteroids/meteors I thought it would be best to ask the experts in the field to make sure I don't get lynched when this book comes out. Please help however you can. The date during this particular incident is Feb 14, 2016, 11:47 pm...

Hi, Homework Statement Design and build a co-processor that interfaces to the Leon that implements an FIR filter. Use memory mapped registers on the AMBA APB bus device 12 to communicate with the co-processor. Your C program (and Modelsim Testbench) will transmit the 16 bit filter coefficients...

the general form of state space output is y=cx+du which means that output is linear combination of state variables and inputs my question is can we write output in this form when our output is not combination of state variable for example in rlc circuit state variables are vc and IL now if we...

I am working in FORTRAN I need to avoid writing to the same file at the same time while working in a parallel environment. I have a program (that I have not written and cannot edit) that calls a subroutine (that I have written and can edit). The subroutine is called over and over again by...

Hi, I was reading a paper on control of the 1-D heat equation with boundary control, the equation being \frac{\partial u(x,t)}{\partial x}= \frac{\partial^2 u(x,t)}{\partial x^2} with boundary conditions: u(0,t)=0 and u_x(1,t)=w(t), where w(t) is the control input. The authors...

Need help writing C++ program that counts non-whitespace characters...? Homework Statement Here are instructions... Write a program - stored in the file charcounter.cpp - that will read and count non-whitespace characters from the standard input stream - until some special character is...

Homework Statement Homework Equations How did they come up with \frac{1}{2}+k for the equation of the vertical asymptote? I understand everything else except this.The Attempt at a Solution On this particular exercise, I graphed it and saw that each of my vertical dashed lines were all one whole...

I just submitted a lab report for a TLC experiment, but I just realized that I completely forgot to include the "reactions" section. It's too late to save that grade, but for future reference, how would one go about writing out a chemical equation for a TLC experiment? I had always understood...

I have a lab report due a week from now. I want to go above and beyond of what is required of my class and to make it as professional as possible. This is to help me prepare for my future lab reports. I will be using word processor for equations and tables to the best of my ability. Would it...

1. Let m, n, p, q \in Z If 0 < m < n and 0< p \leq q, then mp < nq 2. Propositions/axioms I can use that relate to inequalities 2.4 Let m,n,p \in Z. If m < n and n < p, then m < p 2.5 For each n \in N there exists an m \in N such that m > n 2.6 Let m,n \in Z. If m \leq n \leq m then...

Homework Statement For each positive int k, there are k consecutive pos ints that aren't perfect-squares. I'm trying to write this in symbolic logic, but am getting messed in the second part and might be a little off on the first. Homework Equations The Attempt at a Solution...

I been trying to look into e-mail etiquette in Japanese culture. I do not speak Japanese actually. The person I was refereed to did reply in English. I was wondering if last name-san is sufficient or do I need something else. I am trying to purchase a metal that they only forge for my...

My professor highly recommended to us that we take a technical writing course because apparently it looks really good on the resumes. What is your opinion on this? This applies for any Electrical/Electronics Engineers/Technicians.

To what extent do skilled mathematicians/physicists write things out as they think? Could it be much less than one might initially suspect? Suppose, for example, somebody argued that writing things down ought to be avoided when one is solving problems. The argument would be that writing is...

How do you write error messages for when a function has been given an input that is illogical for what the function does. in matlab function b = bla(a) for example if a < 0 i want it to display a message

Greetings, I'm an undergraduate electrical engineer with minimal programming experience and I'm here because I would like some advice as to how I should approach writing a program I'm interested in. I'm specifically interested in what programming language I should learn and use. The purpose...

This is something I have been thinking about and researching. I have found some answers, and it seems to be different depending on the requirements of the university, etc. Still I wonder when is it that undergrad students start writing their thesis? If you have written a thesis, what...

Has anyone ever had the opportunity to have a theoretical quantum computer running on your PC (being simulated) and write software for it? If you have, could you tell me what you used for the quantum computer and maybe some "Hello World" code (a book explaining the 'language' and some of the...

Hello, What would be the best way to write Engineering Research Papers at an Bachelor Level. I mean how to go about choosing the topic? And doing actual research about it? I mean I know it all depends on the interest of a person,but choosing a topic or a technology to write upon is a...

Homework Statement After extensive investigation, a researcher has found that the mean travel time for mice through one particular maze is 29.0 seconds. She believes that the mice will move faster through the maze when subjected to a loud noise. In order to assess this, the researcher has...

Hello, I am currently writing a paper for submission to the PRL. I wish to put in a note after the names of the first two authors, stating "These authors have contributed equally to this work". I would like to solicit the help of the Physics Forums community in knowing how to do this. In some...