Vertex Definition and 125 Threads

Homework Statement I am a bit rusty on parabolae. I am doing a question on projectiles and have found the coordinates of the vertex of a parabola as: (\frac{(v_0)^2\sin\alpha\cos\alpha}{g},\frac{(v_0)^2(\sin^2\alpha)}{2g}) The question now requires you to show that the distance...

Homework Statement Find the roots and the vertex for 3x^2 + 5x - 2 Homework Equations ax^2 + bx + c a(x - h) + k The Attempt at a Solution OK, this is what I attempted. 3x^2 + 5x - 2 = 0 3x^2 + 6x - x - 2 = 0 3x(x+2) - 1(x+2) = 0 x = 1/3 and x = -2 OK, so I found the roots...

If the momenta on the three external legs p(incoming fermion), p'(outgoing fermion) and p-p' (photon) of a vertex diagram are replaced by -p, -p' and p'-p respectively (i.e., all the external momenta are multiplied by -1) does the amplitude remain unchanged?

I want deduc vertex of the lagrangian, but I not know how?

Homework Statement Write the equation of the parabola described. Vertex: (2, 4) Focus: (2,6) Homework Equations (x-h)^2 = 4p(y-k) The Attempt at a Solution (x-2)^2 = 4(2)(y-4) x^2-4x+4 = 8y -32 Do I need to isolate one of the variables, or can I leave the equation like this?

Homework Statement Is there a network with 50 arcs and one vertex?

1. I need to find the equation of a parabola with a vertex of (-3,-2). It has to open down. 2. I understand of hopefully will understand it. 3. My answer was y=-3x Squared -3x-2 Which I found to be wrong.

Homework Statement Identify the vertex of the parabola y = (x + 2)2 – 3 Homework Equations The Attempt at a Solution I would love to have an attempt but I have gone through my book and notes and I'm still confused on how to do this. If i could see an example even so i can work...

say I have a QED vertex with an anti-fermion (p) going in and a fermion (q) and photon(k) coming out. Since the momentum flow is supposed to be along the direction of particle number flow, wouldn't this mean that the delta function at that vertex would be \delta(-p-q-k) ? that doesn't seem to...

Homework Statement How do you figure out the equation of a parabola by only knowing the vertex and ONE of the x intercepts Vertex: (0, -1920) X intercept: (96,0) Help=)

I am currently studying particle collisions. Before I begin I need latest mass values of the leptons, bosons and quarks. However I have been told that I will need to slightly modify these due to vertex corrections. (Due to the incoming particles interacting before colliding, see attachment for...

A detailed introduction of the new LQG spinfoam model---flipped version of the Barrett-Crane vertex amplitude---appeared in August*. Quite a lot of follow-up work has been posted, including three papers that appeared yesterday. Recently posted extensions include numerical work by Rovelli et al...

Can we find the equation of a parabola when two points on it and the time of travel between the two points are given.It is also given that neither of the two given points is the vertex.

Homework Statement find the vertex by completing the square: f(x)=2x^2-4x+7 Homework Equations The Attempt at a Solution numerous attempts yet not one looks right. one was as such: y-7=2x^2-4x; y-7+4=2x^2-4x+4; y-3=2x^2-4x+4; y=2(x-2)^2 +3... I could see this as...

this just out http://arxiv.org/abs/0705.2388 The loop-quantum-gravity vertex-amplitude Jonathan Engle, Roberto Pereira, Carlo Rovelli 6 pages "Spinfoam theories are hoped to provide the dynamics of non-perturbative loop quantum gravity. But a number of their features remain elusive. The best...

Positive point-charges of +16.0 mC are fixed at two of the vertices of an equilateral triangle with sides of 1.30 m, located in vacuum. Determine the magnitude of the E-field at the third vertex. so...all the particles are in equalibrum so that means F=ma=0 so if i call the third vertex...

"A new spinfoam vertex" probably MIP for second quarter The new paper of Livine and Speziale could very well turn out to be the most influential paper of second quarter 2007. http://arxiv.org/abs/0705.0674 A new spinfoam vertex for quantum gravity A large part (perhaps majority) of research...

How do you find the value of the distance between the focus and vertix for the parabola given by the equation 6x^2 + 8 = 2y.

please help me with this question Show that in every simple graph there is a path from any vertex of odd degree to some other vertex of odd degree? here is my answer please check and correct if its wrong thanx ANSWER: In a simple graph, the sum of the degrees of the vertices must...

Find the vertex, focus, and the directrix of the parabola. I get tripped up sometimes, but I know how to find all of the stuff with an equation like this : (x+1)^2 +8(y+3) = 0 But how do I find it with equations like this y^2=-6x or x+y^2=0 Can you complete the square with...

Could anyone help/advise me please how to draw graphs for self-energy and Vertex functions given in attachments one and two. In attachment one Sigma is self energy in coordinate space, S - fermion propagator, here I have one question: I was reading something where I found these exppresions, but...

Fins an equation for the parabola with focus at (-5,0) and vertex at (-5,-4). I have come up with: x^2 + 10x + 16y + 89 = 0 How far off am I?

I need help with the following question. The parabola y^2 - x + 4y + k = 0 passes through the point (12,1). Find the vertex of the parabola.

1.In the figure, describe the motion of particles X and Y at the instant. What will be the shape of the string after 1/4 cycle? I don't know which direction that the crests are traveling as there are two sources. 2.The tetrahedron BCDH is cut off from the cube and is then placed on top of the...

Can somebody please give me an online reference for a good proof of 'The Four Vertex Theorem'? :confused: