# Recent content by markov4

1. ### I need a post/image of mine removed

^^That's alright i guess. The assignment was due friday, so it doesn't matter anymore. I'm just kinda worried that some idiot may have copied my exact solution (since some other idiot posted a link to the topic in our newsgroup for the subject a day before it was due), and the university takes...
2. ### I need a post/image of mine removed

Hi, I won't go into details, but i need a photo deleted from a topic i made, where i included my solution to an assignment question. Who can help me with this? I private messaged Greg Bernhardt but he hasn't replied to me.
3. ### Contour integration using residue theorem (quick question)

Homework Statement The Attempt at a Solution So i have poles at: z=-1 of order 3, z=1 and z=2. For part i), no poles are located inside the contour, therefore the residue is 0. <--is that right to say, that since there are no poles inside the contour, the residue is zero?
4. ### Splitting 2nd order DE into two 1st order DE's

Ok after doing some reading on ode45, i think i get it. So yes i'll leave Psi(z) as it is, and implementing it into my matlab code, it will be solved according to the initial conditions i set. Just need to try it out in matlab now!
5. ### Splitting 2nd order DE into two 1st order DE's

^^I see then. So i'm assuming that ODE45 in matlab will accomodate for leaving \Psi(z) in the equation? I'm reading up on it now (ODE45) but i don't think i understand it.
6. ### Splitting 2nd order DE into two 1st order DE's

^^So when i put these coupled equations into matlab, what do i define \Psi(z) to be?
7. ### Splitting 2nd order DE into two 1st order DE's

^^But for the second part of the question, we're required to "Write a program that uses an inbuilt numerical solver (such as Matlab's ode45) to numerically solve for \Psi(z) for z1<z<z2..." so we have to choose our own initial conditions to incorporate into our program, along with using ode45 in...
8. ### Splitting 2nd order DE into two 1st order DE's

Homework Statement 1.a) Taking the Schrodinger second order differential equation given, split it into two first order differential equations for numerical solving. We're given the relevant constants in a table, such as \hbar, \alpha, etc. 'z' is taken to be an indepedent variable which we...
9. ### Joint pdf/marginal/expectation related

I think i see now..thanks!
10. ### Joint pdf/marginal/expectation related

So knowing that the area of a triangle is (1/2)*b*h, and knowing that our joint pdf must integrate to one and it also incorporates the area under a triangle..then wouldn't f_{X,Y}(x,y) be equal to (1/2)*b*h <--as in that's the function we take the double integral over, to get it to equal one...
11. ### Joint pdf/marginal/expectation related

Homework Statement Homework Equations Well i know the double integral formula for the joint pdf The Attempt at a Solution So firstly we're told to find the joint pdf of X and Y. I'm not sure where to begin. So how do we find the function that we take the double integral over? I'm...
12. ### Mental calculators?

I read up on that, and it sounds sort of similar actually, thanks.
13. ### Mental calculators?

I guess like with anything, practicing something, you'll eventually master it. I'll give such methods a go on my summer break. lol no :p but for the record, i've never had any type of drugs.
14. ### Mental calculators?

Hi there, i told this to a friend but he only looked at me weirdly so the internet seems proper to post such a strange story. My post relates to people who have incredible abilities at mental calculations, autistic savants or anything of the kind. Last year around August i was sitting in...