Value Definition and 1000 Threads

$x,y,z \in N\\ \left\{\begin{matrix} 3x-4y=0---(1)\\ x+y+z=\sqrt {x+y+z-3}+15---(2) \end{matrix}\right.$ find the value of $x-y+z=?$

1. Homework Statement First, if you want to skip my explanation, I believe the error is somewhere in the last 15 lines of code or so. Heres some background on test cases: Use stating member variables to use a class that helps you convert a double number into english words. For example, if a...

The statistical ensemble interpretation (SEI) is supposed to be a minimal interpretation of QM with the smallest amount of philosophy, vagueness and controversy. Yet it turns out not to be the case. For instance Ballentine, the inventor of SEI, interprets Bell theorem as a strong evidence of...

Homework Statement what is the value of ni for an electron that emits a photon of wavelength 93.14 nm when it returns to the ground state in the hydrogen atom Homework Equations planck's constant 6.63 x 10^-34 The Attempt at a Solution no idea [/B]

An absolute value property is $$\lvert a \rvert \geq b \iff a\leq-b \quad \text{ or } \quad a\geq b,$$ for ##b>0##. Is this true for the case ##a=0##? I mean if ##a=0, \lvert a \rvert =0## so ##0 \geq b##. But ##b## is supposed to be ##b>0##, so we have a contradiction. How can this property...

Homework Statement Show that: d<A(q,p)>/dt=<{A,H}>, where {A,H} is a Poisson Bracket Homework Equations Liouville theorem The Attempt at a Solution <A>=Tr(Aρ)⇒d<A>/dt=Tr(Adρ/dt)=Tr(A{H,ρ}) So, in order to get the correct result, Tr(A{H,ρ}) must be equal to Tr({A,H}ρ), but I don't think I can...

Homework Statement Find the point "c" that satisfies the Mean Value Theorem For Derivatives for the function ## f(x) = \frac {x-1} {x+1}## on the interval [4,5]. Answer - c = 4.48 Homework Equations ##x = \frac {-b \pm \sqrt{b^2 -4ac}} {2a}## ##f'(c) = \frac { f(b) - f(a)} {b-a}## The Attempt...

Homework Statement [/B] In my excercise book, I was given a typical diagram as that in Fig (6-7) above. And the problem statement says: The diagram presents the x-ray spectrum produced by Coolidge tube. Determine the least potential difference needed to produce the characteristic radiation...

Homework Statement . [/B] An 11kv motor is fed by cables from a transformer via switchgrear, having a phase impedence of 0.3 + j0.3 ohm. The Earth return path to the transformer neutral has a resistance of 0.42 ohm. Determine a suitable value of neutral resistance if the voltage rise at...

Hi , I was measuring the inductor and capacitor value of a resistor bank with a 100Hz and 1kHz using a LCR meter by fluke. I realize that with different frequency, the L and C values were different. If the measured values were the inductance and capacitance I can understand that it changes...

I am a high school student in Hong Kong studying Physics. I am having some problems about atmospheric pressure. Imagine there is a cube block with volume 1 m3 and top surface area 1 m2 . The cube block is being placed on the floor and it has mass of 1 kg. What is the normal reaction force F...

Say I am given the integral ##\displaystyle \int_0^{\infty} \frac{x \sin (ax)}{x^2 - b^2} dx##. How can I determine whether this improper integral converges in the normal sense, or whether I should just look for the Cauchy Principal Value?

Homework Statement Referring to the diagrams below, what would a suitable value for Rg and why? I have did a lot of research and can't get a clear answer, can someone clear it up for me?

The roots of the equation 2x^2+ 5x – k differ by 2. Find the value of k. Can someone get me started? I found this question online and find it interesting.

If the expression 8x^2+4x+n has real roots, find the value of n. Can someone get me started? I found this question online and find it interesting.

How to find the value of f'(x) at cif 1. f(x)=sinx, c=pi/4 2. f(x)=sinx, c=3pi/2 3.2. f(x)=cosx, c=0, pi/2, pi, 3pi/2, 2pi

Homework Statement This has been driving me crazy I can't for the life of me figure out how to convert the limits of this integral into spherical coordinates because there is an absolute value in the limits and I'm absolutely clueless as to what to do with with.Homework Equations $$\int_{\frac...

Homework Statement Homework EquationsThe Attempt at a Solution I tried to solve (a), but i don't know which approach is right ((1) or (2)) and how to solve (b).[/B]

The value of irrational number π, correct to ten decimal places (without rounding), is 3.1415926535. By using your calculator, determine to how many decimal places the following quantity (22/7) agrees with π. Extra notes from textbook: Archimedes (287-212 B.C.) showed that (223/71) < π <...

The value of irrational number π, correct to ten decimal places (without rounding), is 3.1415926535. By using your calculator, determine to how many decimal places the following quantity [(4/3)^4] agrees with π. The value used for π in the Rhind papyrus, an ancient Babylonian text written...

Homework Statement Homework Equations The Attempt at a Solution When I take the second formula, multiply by it's conjugate and then by x and do the integral of the first formula, I get 0, and not L/2, for <x>. Am I missing a formula ? The complex conjugate of the exponential part...

I’m probably missing something obvious here but I can’t figure out what. Consider a galaxy, starting at an initial distance of ##D_0##, recessing with a constant velocity. After a time Δt, we’d measure a larger distance ##D_{t}##. From this scenario I’d conclude that the Hubble value based on...

Hi, I'm working on a problem about a spherical balloon as its inflated slowly the radius of the balloon is in cm and the time is in seconds dr/dt = k/r2 Now I know how to rearrange this equation using separable differentiation r=3√3kt+c However I would like to find the value of the...

Homework Statement Given a sequence of Heads and Tails, let’s say that the sequence has a switch each time one toss is different than the toss before it. For instance, the sequence HHTHTTTHTH has 6 switches. Suppose you toss a fair coin N times and record the resulting sequence of Heads and...

If we define ##|a| = \sqrt{a^2}##, then why can't we do something like ##\sqrt{a^2} = (\sqrt{a})^2 = a##? Or equivalently ##\sqrt{a^2} = (a^2)^{1/2} = a^{2/2} = a##? Isn't this a contradiction? Also, how would this relate to showing that ##\sqrt{|a|} = |\sqrt{a}|## is true or false?

Homework Statement Find all the numbers c that satisfy the conclusion of the Mean Value Theorem for the functions f(x)=\dfrac{1}{x-2} on the interval [1, 4] f(x)=\dfrac{1}{x-2} on the interval [3, 6] I don't need help solving for c, I just want to know how I can verify that the hypotheses of...

I really need help on how to solve this (Sweating): A dice game involves rolling 2 dice. If you roll a 2, 3 , 4, 10, 11 or a 12, you win \$5. If you roll a 5, 6, 7, 8, or 9, you lose \$5. Find the expected value you win (or lose) per game.

Hello, I am stuck on this question.The bold part is where I am stuck. I was able to get at least 2 out of the 3 test outputs but I can't seem to get the last one. I tired taking out the dividing by 2 but then the first test output doesn't work. Thank you. Question: For any element in keysList...

Solve the initial value problem for $y$ as a function of $x$ \begin{align*}\displaystyle \sqrt{16-x^2} \, \frac{dy}{dx}&=1, \, x<4, y(0)=12 \end{align*} assume the first thing to do is $\int$ both sides

if ## a,b,c,d,e ## are positive real numbers, minimum value of (a+b+c+d+e)( \frac{1}{a} +\frac{1}{b} +\frac{1}{c} +\frac{1}{d} +\frac{1}{e} ) (A) 25 (B) 5 (C) 125 (D) cannot be determined My approach : expanding the expression , i get 5+a( \frac{1}{b} +\frac{1}{c} +\frac{1}{d} +\frac{1}{e}...

I have to calculate the Expectation Value of an Energy Eigenstate : < En > The integral is ∫ ψ* En ψ dx I have : A ) ψ = √L/2 sin nπx/L , a single standing wave of the wave function B ) ψ = BsinBcosD , the wave function of the particle C ) ψ = ΣCn ψn = C , sum of all the...

three spheres of mass 1kg,2kg and 3kg move in the same line with velocities 5i,i and 3i respectively. the smaller masses are the first to collide.if only one collision takes place find the maximum value for the coefficient of restitution between the smaller masses. what I've got so far...

Homework Statement In order to provide full scale deflection the coil current required in a galvanometer is 190μA and the resistance of the coil in the galvanometer is 35Ω - What is the value of the resistor to be connected in parallel with the meter so that full scale deflection is obtained...

While going through the derivation to find the surface tension of liquid i came with the formula which says that the surface tension is directly proportional to radius of the capillary so does that imply if we use a capillary with a greater radius so the same will give the different value of...

Hello, I'm a beginner at quantum mechanics. I'm working through problems of the textbook A Modern Approach to Quantum Mechanics without a professor since I am not going to college right now, so I need a brief bit of help on problem 1.10. Everything else I have gotten right so far, but I am...

Hello all, I'm wondering if someone can offer some insight here: We have a random variable X, and it's expectation is called y. Can it be shown that 1/y = E[1/X] ?? Thanks

I have been reading in various sources that the directly measured value of Ho is high than the global value inferred by precise measurements of the CMB. The local value seems to be around 73 km/s/Mpc where as the global value inferred, assuming a flat Lamda CDM model is about 67 km/s/Mpc...

I've done the problems, but they don't make sense to me. The answers don't really make sense. I'll post the question, the given formulas and my attempts: Given formulas: (1) future value to present value: PV= FV / (1+i)n (2) annual payment to present value: PV = A/i * [1 - 1/(1+i)n]...

Homework Statement Given a matrix M={{2,1},{1,2}} then value of cos( (π*M)/6 )Homework EquationsThe Attempt at a Solution Eigen values are π/6 and π/2 and eigen vectors are (π/6,{-1,1}) and (π/2,{1,1}). Diagonalize matrix is {{π/6,0},{0,π/2}} I got same value (√3/2)M

Homework Statement finding the resistor and current which is following through the circuit[/B]Homework Equations kirchhoff law The Attempt at a Solution almost as fig 1 ( 9v=3.458 mA and 12v=11.122 mA) fig 2 (9v=1.472 mA and 12v=12.882 mA) i3=2.48 mA

Homework Statement A Solve the following initial value problem: ##\frac{dx}{dt}=-x(1-x)## ##x(0)=\frac{3}{2}## B. At what finite time does ##x→∞## Homework EquationsThe Attempt at a Solution ##\frac{dx}{dt}=x(x-1)## ##\frac{dx}{x(x-1)}=dt## Partial fractions...

Hello, could someone please help me with this question? I don't even know where to begin. Given vectors a = (2, x, 0), b = (1, 0, −1) and c = (5, −9, 3), and let P(2, 1, −1) be a point. Find the value of x in a such that the angle between a and b is π/4, then find the area of parallelogram...

In kinetic theory, the number of molecules hitting a unit area of a surface per unit time with speeds between v and v + dv and angles between \theta and \theta + d \theta is found to be a function of sin(theta) and cos(theta). There will often be a practice problem asking to show that the...

The following quote is from the Wikipedia article https://en.wikipedia.org/wiki/Big_Bang_nucleosynthesis#Characteristics . The temperature/time relation in this era can be given by the equation: where t is time in seconds, T is temperature in MeV, and g* is the effective number of particle...

$if \,\, (x+\sqrt {x^2+1})\times (y+\sqrt {y^2+4})=7$ $find: \,\, x\sqrt {y^2+4}+ y\sqrt {x^2+1}=?$

I couldn't find this online, but basically, I have 4 text fields that can be updated as the user wishes, but I want to get the value from the most recently updated one, and have the others revert to their previous values. Say initially all fields are zero. A user edits one field and hits the...

Homework Statement Projectile motion questions, Kinematics questions: my physics teacher defined acceleration due to gravity as -9.81 m/s2. Specifically in questions regarding: dropping an object, throwing an object downwards, obliquely launching an object. Today we are studying a box on...

I was reading Bransden's Quantum Mechanics 2nd edition, chapter 2 page 61. There,it says "It should be noted that since E =hv (v for nu), the absolute value of the frequency has no physical significance in Quantum mechanics..." Why is that? Isn't this a contradiction?

Hello forum members, The electric potential for a point charge is a scalar function given by $$V = \frac {kq}{r}$$ This means that the potential has a nonzero value everywhere. The potential becomes ##V=0## when ##r=\infty##. However we know that what matters is the potential difference...

Homework Statement Does anyone know of a simple proof for this: https://s30.postimg.org/tw9cjym9t/expect.png E(X) = E(X|S)P(S) + E(X|S_c)P(S_c) X is a random variable, S is an a scenario that affects the likelihood of X. So P(S) is the probability of the scenario occurring and and P(S_c) is...