Value Definition and 1000 Threads

I try to get a correct result for the radius of a standard white dwark (roughly 10000 km). I just want the order of magnitude , i.e with the common values of a solar mass into Earth radius sphere. From http://www.astro.umontreal.ca/~bergeron/CoolingModels/Synthetic_Calibration.pdf page 1223...

X is a random variable that follows the Log-Normal probability density function. n indipendent trials are carried out. We want to know the probability density function of the random variable Y, that is defined as the average value of the “n” outcomes of the trials described above.

Homework Statement A random variable Y has a binomial distribution with n trials and success probability X, where n is a given constant and X is a uniform(0,1) random variable. What is E[Y]? Homework Equations E[Y] = np The Attempt at a Solution The key is determining the probability of...

Hello. I'm using Griffiths' introductory textbook on quantum mechanics, which I have just begun, and have arrived at a question on a simple wave function: The answer to the first question I know to be √(3/b). The answer to part e is (2a + b) / 4. My problem is that I don't understand how...

Homework Statement Find a > 0 so the integral int(exp(-ax)*cosx)dx from 0 to inf get as high value as possible. The Attempt at a Solution My way of solving this is to plot the integrand, i.e. exp(-ax)*cosx and check for different values of a. The larger a is, the smaller the area under the...

i have a value that is generated as the max value for example from this list [0.6000001, 0.3, 0.3, 0.4] clearly the maximum value is 0.6000001 but python does not seem to be able to recognize this value as the maximum. i have tried so many ways to solve it but to no avail. even when changing...

Homework Statement I want to prove that ##\frac{\partial \langle x \rangle}{\partial t} = \frac{\langle p_x \rangle}{m}##. Homework Equations $$i\hbar \frac{\partial \Psi}{\partial t} = -\frac{\hbar^2}{2m} \frac{\partial^2 \Psi}{\partial x^2} + V \Psi$$ The Attempt at a Solution [/B] So...

Homework Statement I have got the following matrix. I have found the eigen values but in some eq x, y & z terms are vanishing, so how to find the value of eigen vector? Also why we have to do normalization?? A__=__[1__1__0] ______[1__1__0] ______[0__0__1]Homework Equations A-λI=0 Ax = -λIx...

Homework Statement I think I am evaluating a wrong value for eigen vector. Wrong in the sense that first row is giving different value and next row is giving a different value. The matrix is: [0 1] [-2 -3] My eigen values are λ=-1 & λ=-2. I get the fine vectors for λ=-1 but λ=-2 x...

Homework Statement For the equation y=cx[L−x] say for a circle with the value of L at 100 meters and the value of x at 25 meters. What would be the value of the constant c for a perfect circle. 3. Attempt at the Solution: I can approximate and graph this with different values of c however I'm...

$\textsf{find the value that $\displaystyle \lim_{x \to 0} g(x)$ must have if the given limit statements hold.}$ $$\displaystyle \lim_{x \to 0} \left(\frac{4-g(x)}{x} \right)=1$$ OK the only answer I saw by observation was 2 but the book says it is 4 not sure how you get it with steps

Homework Statement If a = 9-v² then prove that v = 3 (e^6t - 1)/(e^6t + 1) the condition when t=0 also v has zero value Homework Equations I don't quite understand in this but general equation should be dv/dt = a The Attempt at a Solution Actually i don't don't have any idea in this problem...

Hey! :o The random variables $X_1, X_2, \ldots , X_{10}$ are independent and have the same distribution function and each of them gets exactly the values $\pm 2$ and with equal probability. We define the random variable $S=X_1+X_2+\ldots +X_{10}$. I want to calculate $\mathbb{E}(S^2)$...

Homework Statement Why does ##\lim_{n \rightarrow \infty} f(x_n) = f(c)## contradict ##\lim_{n \rightarrow \infty} \vert f(x_n) \vert = +\infty##? edit: where ##c## is in ##[a,b]## Homework Equations Here's the proof I'm reading from Ross page 133. 18.1 Theorem Let ##f## be a continuous real...

Homework Statement Find k so that y - 36x = k is a normal to the curve y = 1 / abs(x-2). Homework EquationsThe Attempt at a Solution My problem is regarding the absolute value. I know that the tangent to the curve must be (-1/36). In the solutions manual, it is said that by knowing the sign...

The permittivity of free space, ε0, is usually given without any derivation or historical context as to how it was experimentally determined. Could you explain to me how the value of ε0 was first determined experimentally or provide a resource that gives such a derivation? Thanks!

Homework Statement Find solutions to the given equality 2. Relevant equation $$ x^2 +3|x-1|=1 $$ The Attempt at a Solution The above can be rewritten as: $$ |x-1| = {1-x^2\over 3}$$ If my understanding of absolute values is correct, the above simply means that: $$ x-1 = {1-x^2\over 3}...

Recently I watched a youtube video about the speed of light and how it was not about light. I was wondering if the value of C can be determined instead of measured. Is C a constant in some formula that has well-known parameters and so the value of C can be calculated? I am just a science...

Homework Statement How do I find the value of n?Homework Equations I know that when it crosses x-axis y = 0 X3 - X2 - 20 =0 But don't know how to solve it from here The Attempt at a Solution The marking scheme says 3.0 or 3.1 I couldn't get the answer even by substituting I know I'm doing...

Find, with proof, the smallest possible value of $1-\frac{1}{n_1}-\frac{1}{n_2}-\frac{1}{n_3}$ where $n_1,n_2$ and $n_3$ are different positive integers, that satisfy:$\frac{1}{n_1}+\frac{1}{n_2}+\frac{1}{n_3} < 1.$

The following program is printing wrong value of RWTSED. How can I print correct value?? program inpdat c IMPLICIT NONE REAL RHOMN,RWTSED,VOLSED VOLSED = 17424.0 RHOMN = 2.42 !0000076293945 RWTSED= VOLSED*RHOMN*1.0E6 2000 FORMAT(/,3F40.5)...

I am trying to write a program that calculates the root of chi-square. I am not getting the correct answer and I honestly am at my wits end trying to figure it out. I know my simp_p() method is returning the correct value, but for some reason my root_chisq() method is not giving me the correct...

Homework Statement I am trying to find the value of a determinant, Homework Equations See the notes given in my Textbook, The Attempt at a Solution I applied this method to find the value of a determiannt, See it here, Why is my result wrong? I will be thankful for any help!

$\tiny{de1.2.1}$ $\textsf{ Solve each of the following initial value problems and plot the solutions for several values of $y_0$.}\\$ $\textsf{ Then describe in a few words how the solutions resemble, and differ from, each other.}\\$ $$\begin{align*}\displaystyle \frac{dy}{dt}&=-y+5...

Jack, John and CWS's ============== Canadian Wild Strawberries (CWS) are tiny but tasty. A and B each have a jar containing 400 CWS; they decide to have a CWS eating race; A wins, swallowing his last CWS when B still has 23 left. Took A 13.2 seconds; burp! Next, B takes on C, each with a jar...

From the book Introduction to Quantum Mechanics by Griffiths,. In the section 6.4.1 (weak field zeeman effect) Griffiths tells that the time average value of S operator is just the projection of S onto J while finding the expectation value of J+S $$S_{avg}=\frac{(S.J)J}{J^2}$$ How to prove this?

Let's say we have N cookies. We are giving the cookies to kids in different schools in different states. Each school has a fixed number of kids. We want a final value of cookies per kid for each state. Once we have that value, Cs, "cookies per kid" for each state, what is the interpretation of...

https://uploads.tapatalk-cdn.com/20180712/28a4bbb89e76d3478ae2fd0825562148.jpg Question 81

Homework Statement Find the minimum value of the area of the region under the curve ## y=4x - x^3 ## from ##x=a## to ##x=a+1##, for all ##a>0##. This problem is from Stewart's Calculus Homework Equations Finding the area under the curve... The Attempt at a Solution I can set up the equation...

Say I have a given problem that states: Does the Intermediate Value Theorem guarantee that the following equation has a real solution between ##(\frac{7}{2})## and ##(\frac{9}{2})##? $$3x^4-27x^3+177x^2+1347x+420=0$$ Now what I want to do is determine the sign of x=##(\frac{7}{2})## and...

I want to design a curding machine (Milk to Cheese) with an open system that operate at isobaric process (contant pressure), P = 1 atm = 1,... bar the range of temperature is = 25-75 0C can i find an enthalpy of water from Mollier Diagram if my temp. is 25 to 75 degree celcius ? how ? from my...

Hi all, I am creating a game for fun, which need some math skill to work out the chance of winning and the way to keep the banker never lose. The configuration of the game is like this: five boxes marked no.1, no.2, no.3, no.4 and no.5; there are many balls in different color in each box. For...

For the folowing two problems determine the truth value of each statement: assume a and b are true and c and d are false. not(a V b) -> s not( T V T) -> s F -> s T r -> [(d -> w) <-> (a ^ c )] r -> [(F -> w) <-> ( T ^ F)] r -> [T <-> F] r -> F I am fairly certain I did the first one correct...

Hello! (Wave) I want to prove that if for the initial value problem of the wave equation $$u_{tt}=u_{xx}+f(x,t), x \in \mathbb{R}, 0<t<\infty$$ the data (i.e. the initial data and the non-homogeneous $f$) have compact support, then, at each time, the solution has compact support. I have...

Hi all Trying to improve my level of maths and would like some help with the below question please. A 10-year lease with annual rental payments to be made at the end of each year, with the rent increasing by 2% each year. If the first year rent is £20 and the OCC is 10% per year, what is the...

Hello! (Wave) I want to find the solution of the following initial and boundary value problem: $$u_t(x,t)-u_{xx}(x,t)=0, x>0, t>0 \\ u_x(0,t)=0, t>0, \\ u(x,0)=x^2, x>0.$$I have done the following so far: $$u(x,t)=X(x) T(t)$$ $$u_t(x,t)=u_{xx}(x,t) \Rightarrow...

$\tiny{2.1.{7}}$ $$\displaystyle y^\prime +y =\frac{1}{1+x^2}, \quad y(0)=0$$ $\textit{Find the solution of the given initial value problem.}$ \begin{align*}\displaystyle u(x) &=e^x\\ (e^x y)'&=\frac{e^x}{1+x^2} \\ e^x y&=\int \frac{e^x}{1+x^2}\, dx\\ %\textit{book answer} &=\color{red}...

Hello! (Wave) Let $a,b>0$ and $D$ the rectangle $(0,a) \times (0,b)$. We consider the boundary value problem in $D$ for the Laplace equation, with Dirichlet boundary conditions, $\left\{\begin{matrix} u_{xx}+u_{yy}=0 & \text{ in } D,\\ u=h & \text{ in } \partial{D}, \end{matrix}\right.$...

I know that the following two functions have the same derivative: ##\arctan (x-1)## and ##2 \arctan (x-1 + \sqrt{(x-1)^2+1})##. Out of curiosity, how can I find the constant value at which they differ? I tried to add ##\pi / 2## to arctan(x-1) but I'm not sure if that works or not...

Hey! :o Let $D=\left \{x=(x_1, x_2)\in \mathbb{R}^2: x_2>\frac{1}{x_1}, \ x_1>0\right \}$. We have the function $f: D\rightarrow \left (0,\frac{\pi}{2}\right )$ with $f(x)=\arctan \left (\frac{x_2}{x_1}\right )$. I want to show using the mean value theorem in $\mathbb{R}^2$ that for all...

Homework Statement Two charged balls are placed in point A and B and the distance between them is 9,54cm. Each of the balls are charged with 8,0 x 10^-8 C. Find the scalar value and direction of the electric field in point C placed 5 cm from A and 6 cm from B. Homework Equations Cosine Rule...

Homework Statement I have E as a material parameter. It is a modulus of Elasticity It is given as: 109/E = 80/psi I want to write E as a value with units psi. Homework EquationsThe Attempt at a Solution Is this correct? 1/E = 80*109/psi So psi/E = 80*109 So E = 1.25*10^7 psi

Homework Statement The problem is attached as pic Homework Equations ∑(ƒ^(n)(a)(x-a)^n)n! (This is the taylor series formula about point x = 3)The Attempt at a Solution So I realized that we should be looking at either the 30th,31st term of the series to determine the coefficient. After we...

I am practicing old exams. I tried my best but looking at an old and a bit unreliable answer list, and i am not getting the same result. Homework Statement At time ##t=0## the nomralized harmonic oscialtor wavefunction is given by: ## \Psi(x,0) = \frac{1}{\sqrt{3}}(\psi_0(x) + \psi_1(x) + i...

Hello! (Wave) We consider the initial value problem $$x'(t)=-y(t), t \in [0,1] \\ y'(t)=x(t), t \in [0,1] \\ x(0)=1, y(0)=0$$ I want to solve approximately the above problem using the forward Euler method in uniform partition of 100 and 200 points. I have written the following code in...

Homework Statement Homework Equations in picture The Attempt at a Solution (200000(1-0.96^19))/(1-0.96) = 2697903.99 not sure what i did wrong here, answer seems close.

Links for context: 1. https://en.wikipedia.org/wiki/Yukawa_potential 2. https://en.wikipedia.org/wiki/Yukawa_interaction#Classical_potential I'm working on my BSc right now and I'm solving the energies of 2 nucleon systems (so basically just deuteron) by treating them as non-relativistic two...

Homework Statement Homework Equations Q = Qmax (1-e-t/τ) Q= CΔV The Attempt at a Solution CΔV = CΔV (1-e-t/RC) 0.2 = (1-e-t/(1*106*10*10-6) ln (0.2) = ##-\frac{t}{10}## t = - ln(0.2)*10 = 16.09 s Can someone tell me where is my mistake ?

1. Homework Statement : Two identical uncharged capacitors A and B each of capacitance C and an inductor L are arranged as shown in the adjacent figure. At t=0, the switch S1 is closed while switch S2 remains open.At time t=to=√(LC)Π/2, switch S2 is closed and S1 is opened. After switch S2 is...

Homework Statement Let A and B be nxn matrices with Eigen values λ and μ, respectively. a) Give an example to show that λ+μ doesn't have to be an Eigen value of A+B b) Give an example to show that λμ doesn't have to be an Eigen value of AB Homework Equations det(λI - A)=0 The Attempt at a...