astrokid

I heard that there were some 8-12 publishing houses who had refused to publish Harry Potter, before it was finally accepted by Bloomsbury. Does anyone know who were these people?

I'm on a tight budget, so don't think I can take the TGV trains. I read on the internet that there are local slow trains from paris to lille, and then onwards by metro to belgium border, and then train to brussels. Can anyone give me some details on this? What will the rates be like? I don't mind stopping at lille for a few hours to have a look around. Also any alternate routes, or bus routes are also welcome

There is an array x which has n integers.

The relation is S(start,terms,n) = Sigma(x[j]*S(j+1,terms-1,n) , j goes from 'start' to 'n-terms') . Sigma denotes summation.

Basically I am trying to write a code to calculate the sum of products of the coefficients of a polynomial taken 'terms' terms at a time.

eg when start = 1, terms = 3, n=4, answer should be x1*x2*x3 + x1*x2*x4 + x1*x3*x4 + x2*x3*x4

when start = 1, terms = 2, n=4 answer should be x1*x2+x1*x3+x1*x4+x2*x3+x2*x4+x3*x4

The recursion relation gives the right answer, just that I don't know how to write a code for that. Any ideas? C++ code is preferred, pseudo code will do as well

has it got something to do with decreasing coefficient of friction?

I don't have the book, so I have no idea what is mentioned in the book. This is an assignment for my little brother from school. Usually snow flakes have 6 sides, as far as I know. What is mentioned in the book?

I am trying to play harry potter but as soon as i try to launch the game i get a 'sync out of range error'. I am using Intel motherboard D945GCNL but my monitor is 4 years old samsung samtron. Seems like the monitor is not being able to support the resolution or the refresh rate .The point is that I am getting absolutely no chance to specify the resolution or refresh rate, as the game is not running at all. Does anyone have any idea about how to make the game run at a lower resolution?

Previously I had ASUS A7n266-VM motherboard. The game used to run there.

The equation is y''[t] = - w^2* y

The people who are familiar with physics might realize that y'' represents the acceleration if y represents the displacement. So the normal substitution that is generally used in physics to solve this is y'[t] = v

Then the equation simplifies to v dv = - w^2 * y dy

So we can obtain v[t] and then obtain y[t]

But that's not the point.What I am asking is why did we substitute this? Is this a standard practice to solve such equations? Or is this just a trick we obtain from learning physics <The v dv = -w^2 y dy equation is actually the energy of motion>.

Suppose we don't know any physics, and are given this equation to solve, to find out the curve where the rate of increase of slope is equal to negative of the functional value. How do we do it, if we don't know the substitution?

y''[t] = -k sin[y]

I tried using dy/dt = w . It becomes w dw = -k sin[y] dy

Then it became all the more complicated with

w as a function of sqrt Cos[y] etc.

I need y as a function of t.

Can anyone please solve this?

Considering one body to be very heavy with respect to the other, the barycentre lies almost at te centre of the heavy body. So angular momentum being conserved, we can apply kepler's second law, can't we?

If we can, then r^2 * w = constant, so w is a function of r

Now this means that if the trajectory of the small body is eliptical, its angular velocity will change with time < as r will change>. Now for change in angular velocity we need angular acceleration. Angular acceleration will be caused due to some torque acting on the body.

How can gravitational force, being radial, produce a torque?

Where am I going wrong?

In elliptical orbits, velocity is not always perpendicular to radius vector <joining the point on the trajectory to the focus>.

Roy and clarke say that v = r * w at the extreme points. How?

We cannot apply v = r x w, can we? This would mean that velocity is perpendicular to the radius. Well it is so indeed at the extreme points, but can we apply this relation to some special points?

If we take two plates with different areas, one plate larger than other then what will happen? It should still store charge when connected to a battery. But how will we calculate the capacitance theoritically without experiments?

And if we take two plates of same area, and tilt one of them , then can we take the area components parallel and calculate the capacitance? <For this I need the previous answer>

Please don't tell that it is how integers are distributed, or that is definition of integers and so on. I found this problem in a book, and so please try to provide some proof based on number theory. I have some basic number theory background.

It is supposed to have a factor between 9000 and 10000

<not necessarily prime>

Please someone factorize it.

It will be highly appreciated if you can tell me how to get the factors without using computer programs.

The number is 1 followed by 8 zeros then 99

I want to prove that (2n)! / {n!*(n+1)!} is an integer.

You can prove than 2nCn is divisible by n+1

alternately you can prove that 2nCn+1 is divisible by n

Or you might leave out combinatorics and use induction straightaway. Just do what you like.

Whatever you do, please give me a solution.

Suppose I choose a prime Pn. Is the number P1*P2*...*Pn +1 always a prime?

here P1 = 2, P2 = 3 and so on. Pn is the nth prime number.

can anyone prove the primeness <or compositness> of the number?

What about P1*P2*P3...*Pn -1 ?

For one thing none of the primes 2,3,5,7,...Pn divide the two numbers. So they should be primes, right?

If they are indeed primes, don't we have infinite twin primes?

Someone please tell me where this argument is wrong <if it is>.

I changed the icon of *.ico files from folder options just for fun, but now they are all displaying the same icon. I am not being able to preview the icon in windows explorer. Anyone knows what the default icon for *.ico files is?

When I had tried to change it, it had told me that the path of the default icon does not exist. Please some one check the default path <the one that does not exist> and post it here.

Have any of you heard of this process? It is consuming 60% of my CPU and making my PC very slow. I am no being able to kill the process using task manager. Is it a system process or a virus? I have Windows XP SP2

I have heard that light travels in the path that requires the least time. Fermat proposed this, and I have seen laws of reflection and refraction derived from it. But why is this principle true in the first case? How will a light photon know which path is the shortest path?

Please answer only if you know. 10 pts for best answer.

is it to increase the amplitude of the produced sound by resonance?

Why do some molecules have tendency to rotate the direction of plane polarized light?