Discrete Definition and 829 Threads

Hi, Please can someone help me with this problem. show that a,b,c are real numbers and a#0, then there is a unique solution of the equation ax+b=c. the uniqueness of the solution is my problem. Thank you B

I need help in solving the following problem: Let X be uniformly distributed over [0,1]. And for some c in (0,1), define Y = 1 if X>= c and Y = 0 if X < c. Find E[X|Y]. My main problem is that I am having difficulty solving for f(X|Y) since X is continuous (uniform continuous over [0,1])...

"Discrete" Geommetry... -What can you do if you have a "Smooth" Manifold..but it's very hard to work with?..perhaps you could "discretize" :rolleyes: :rolleyes: the surface splitting it into "triangles" and take the basic coordinates to be the angles (3) of every triangle..but my question is...

I am in discrete math class right now and trying to get the sets of numbers straight. So, does the set of integers include 0? Is it ok to use 0 in proofs, that makes finding a counter-example a lot easier and disprove a statement about all integers. Was just wondering if that is legal...

Geometry and Discrete Mathematics notes?? Resources? Hello everyone, I'm going to take Geometry and Discrete Mathematics, next year in high school (grade 12). So this summer I'm planning to read some books that would help me out next year, to bulit up my basic skills. So anyone know any sites...

I got really really confused by this supposedly easy discrete probability problem: The problem asks: a)toss a die until a "6" appears. Find the probability distribution of X where X is the number of tosses neded to obtain the first six. b) Prove that the summation of P(x) from x = 1 to n...

Hello, Suppose I have a discrete function of a perfect cosine wave. So if I will do a DCT on this function I will get one non zero coefficient which corresponds to the perfect cosine wave, and the rest will be zero. Now I have a pass filter, which filters out anything with a frequency which...

How can the mind objectify discontinuous phenomena if the mind itself is continuous?

A multiple choice test contains 12 questions, 8 of which have 4 answers each to choose from and 4 of which have 5 answers to choose from. If a student randomly guesses all of his answers, what is the probability that he will get exactly 2 of the 4 answer questions correct and at least 3 of the 5...

What types of discrete derative are there? Thanks in advance.

I am required to find a formula expressing the probability of return to some state in a Markov chain at time n in terms of the probability of return to that state at time n - k and the probability of first return at time k. I cannot find this in my notes, and I have tried looking at several...

Resders of the forum could enjoy this pdf http://documents.cern.ch//archive/electronic/other/pauli_vol3//sommerfeld_0463-2.pdf from http://doc.cern.ch/cgi-bin/setlink?base=pauli&categ=&id=sommerfeld_0463-2 In page 3 of the letter (1 of the transcripcion) you can read Pauli sentence of the...

I am planning on self studyint Discrete Math. What would be a good book for this?

How useful is the knowledge of discrete math for computer programmers?

How useful is discrete math to an electrical engineer; particularly how useful is it to an ic designer?

Let \Sigma = { \beta,x,y,z} where \beta denotes a blank, so x\beta \neq x, \beta \beta \neq \beta, and x\betay \neq xy but x \lambday = xy. Compute each of the following: 1: \parallel \lambda \parallel 2: \parallel \lambda \lambda \parallel 3: \parallel \beta \parallel 4...

let us asuume this discrete signal: f(n)=a^n * u(n) ; where u(n) is unit step function ; u(n)=1 where n>=0 u(n)=0 where n<0 ;0=<a<1 and the foruier transform for discrete signals is defined as : F(i)=sum (...

Why the energy eigen values for negetive energies are always discrete while that for positive energies are always continuous? Also what is oscillation theorem?

I'm having some trouble with this discrete question: Find the least natural number n such that √(x² + x³ + 3) is O(xⁿ). With the value of n that you have found, is it true that xⁿ is O( √(x² + x³ + 3) )? Can anyone help?

The question asks: In triangle ABC, with vertices A(0,a), B(0,0), and C(b,c), prove that the right bisecors of the sides meet at a common point. Ok, this question is really getting to me. I know that I could find the equations of all three right bisectors and then solve for x and y through...

Ok so I need to prove (by contradiction) that... if the power set(A) is a subset of power set(B), then A is a subset of B. I was given a hint to use proof by contradiction, but in general I'm lost as to what to do... I know the power set of (A) is {B|B subset A} and the powerset of (B) is...

w[n] = exp(j*pi*n) w[n] = (−1)^n Hi, can anyone off hand verify why these two exressions are equal? Thanks

I have a project to do on algorithms, and as far as I can tell, the project is due before we cover the topic :p. My textbook only makes a slight reference to what an algorithm is :(. Can anyone point me in the direction of a website or book that tells me all there is to know about algorithms?

Hi, I have a few questions about Sonometers which I've attempted to think through - though I may be missing something. Perhaps someone can fill in any gaps for me? If I was to be asked why only 'discrete modes' of vibration can exist for a sonometer, is it enough merely to talk about the...

Hi, This is one of the question from my hw, i don't even understand what it's asking? Please shed some light on it.. thx what is the smallest value of k such that any integer postage greater than k cents can be formed by using only 4-cent and 9-cent stamps? Show that k cents in postage...

A unified theory of physics has been evasive, I believe, because physicists have only considered a continuum of unification. In other words, we have attempted to relate all spacetime to all quantum dynamics - that they are inclusively connected. Has the argument arisen that quantum measurement...

Hello, How do I proove : (A U B) x (A U B) = (A x A) U (B x B) if and only if : (A C B) or (B C A) ? Please Advice, Dimitry Haritonov

I have a question from hw, the question is stated "Show that if the poset (S,R) is a lattice then the dual poset (S,R^-1) is also a lattice" I know by Rosen theory that the dual of a Poset is also a poset but how can i prove that it is also a lattice, what def. am i missing. Any help would be...

could someone show me how u would solve 2^27841 mod 34 by hand? I know what theorm to use, I am just having trouble using it? Thanks

The wind is blowing N 75 degrees East at 96 km/h. A plane is flying with air speed 320 km/h. Find the heading the plane must have in order to get from A to B, if B is S40 degrees W of A. Include a diagram in your solution. Alright, i am totally lost. Could someone please maybe put on some...

I ran into this logic puzzle and have been working on it for couple hours now but i can't seem to explain clearly why the answer i came up with is the answer. Heres the question: The police have three suspects for the murder of Mr. Cooper: Smith, Jones, and Williams. Smith, Jones, and...

Hey if anyone could help me with this I would be sooo grateful. I am trying to grasp the idea of onto, one-to-one and bijection(both) functions. A sample problem is: If f(x) = 2x . What is f(Z), all integers. What is f(N), all naturals. What is f(R), all real. These are 3 different problems...

Hi, For one of the questions in my Discrete Mathematics course, I have to find what property of a formula makes its dual formula also its negative. With a dual formula, the logical operators of "^" and "v" are reversed, the former meaning "and" and the latter meaning "or". With its negative...

Hi, my name is Quan and I am new to this forum. I am trying to build a discrete operational amplifier but I am very weak with circuit designing since my concentration is in communication. Anybody here have a lot of experience building analog op-amp circuits? If you are in the area then that's...

I have to find the signal if x(n) = nv(n-1) for -infinite < n < + infinite x(n)+x(-n) Can I get hint with this problem so I can do rest of them. Thanks

An Advertising sign is supported by a horizontal steel brace extending at right angles from the side of a building, and by a wire attached to the building above the brace at an angel of 25. If the force of gravity on the sign is 850N, find the Tension in the wire and the compression in the steel...

My life is miserable already first week into grade 12. This stupid book they have given is like Socrates, it asks questions but it only gives ugly pictures and more questions. The examples barely relate to the questions, and our Master Teacher only does examples. Of course I am not a brilliant...

1) The board of directors of a pharmaceutical corporation has 10 members. An upcoming stockholder's meeting is scheduled to approve a new slate of company officers (chosen from the 10 board members). A) 4 (Presendent, Vice Presendent, secretary, and treasurer) positions needs filled. How many...

How many elements are in a sub1 intersect a sub 2 which equals a null set when a sub 1 =12 and a sub2 = 18

If spacetime is discrete at the Quantum/Sub-quantum scale, what "joins" and keeps spacetime together at GR scales? P.S. What "Separates" spacetime at Quantum scales?

For a superposition of two since waves of equal amplitude in a dispersive media, we find that the group velocity is given exactly by v_g = \frac{\omega_2-\omega_1}{k_2-k_1} and approximately by d\omega / dk|_{k=k_0}. How do we show that this approximation holds for any type of waves...

hi! i have a homework problem here that I'm stuck on: What is the probability that a hand of 13 cards contain no pairs? i know a 13-card hand is C(52, 13) but i have no idea how to represent the probability of that 13-card hand containing no pairs. can anyone give me a hint?

I don't know why but these types of problems always seem to kick my butt. Any how here they are and my best guesses as to the correct answer. 1. Danny has 12 different lures in his tackle box that he takes on a five day fishing trip. On each day of the trip he fishes with the same...

There are a few areas I wanted to make sure I understand what is going on in with discrete math. I have a test tomorrow over these topics and so this is not exactly homework unless you count studying for a test as homework. In any case I will do my best to explain what I know or don't know and...

discrete Fourier tranforms -help! How does one write the orthogonality condition for discrete Fourier tranforms - alternatley, how does one express the kronecker delta as a sum over exp(i k x) kind of thing. One last thing - what is the mormalization constant in front of the sum (analogous to...

Let \left( {X_n } \right)_{n \ge 0} be a Markov chain (discrete time). I have {\bf{P}} = \left[ {pij} \right]_{i,j} = \left[ {P\left( {X_1 = j|X_0 = i} \right)} \right]_{i,j}, and the initial probability distribution {\bf{p}}^{\left( 0 \right)}. I need to calculate P\left(...

And when I say easy I mean easy for a lot of you but not necessarily for most people. 1) Four microprocessors are randomly selected from a lot of 100 microprocessors among which 10 are defective. Find the probability of obtaining no defective microprocessors. The answer the book gives is...

Decision and discrete mathematics... Why is Decision maths called "Decision maths"? :smile: Thanks.

Let X be a random variable with probability function: fx(x) = c/x!, x = 0, 1, 2, ... Find c. By first guess was to form the sum: \sum_{i=0}^{x} c/i! = 1 But I have no idea if that's the right approach or how to proceed.

ok the problem is Given that a and x are intergers, a>1, a|(11x+3), a|(55x+52), find a. I am not sure how to even start this one to find a...any help please :cry: