Cap'n Refsmmat

It has a slightly different avatar layout, that's all. I should've realized vBulletin wouldn't adjust the navbar the way I thought it would...

Perhaps we should make that link a little more blatant.

My Account->User Control Panel.

http://blogs.scienceforums.net/using-latex/

Your answer checks out, I think. Running it back through the same equations gives me a similar answer.

Blast. It's vB's way of preventing people from providing links on the forum that'll log you out -- you have to have a logout "hash" in the URL to the login page to make it work. I need to figure out how that works. The SFN home page has the last five, and there's an RSS feed of the last 20. WordPress MU doesn't let you customize that option. I looked in the main admin screen and it appears WordPress pings ping-o-matic automatically anyway. For those that don't know, click Plugins on top and enable Spam Karma 2. WordPress comments are popular venues for spammers.

That'll be another special surprise when we release that. Our physicists have been working on a theory that will rule them all. Thanks for the praise, by the way. I'm glad to see our work has paid off.

After weeks of painstaking work constructing an entirely new front page layout and hours developing code to run the page, SFN is proud to unleash its all-new front page for mass consumption. The page ties together all aspects of SFN, featuring the latest blog posts on SFN Blogs, the latest forum posts here at the forum, and numerous other patent-pending features designed just for SFN. We hope that you'll enjoy the new front page and find it more useful than the old. If you have any problems with it, tell us here -- we'll gladly fix the problem and hide any evidence that it ever existed.

Lesson 2 - The basics of differentiation So now onto first principles of differentiation: this is where I tell you how to actually go about differentiating something and what we actually mean by the term 'differentiation'. A classic math problem is to sketch a curve out (like the classic y = x2) and then they say to you: "draw a tangent to the curve at the point x = 1, and hence find the gradient at that point". And you grudgingly scrawl out a quick graph, shove a quick tangent on and get an approximate value for the gradient. After all, we all know it's dead easy to find the exact gradient between two points on a straight line, but on a curve? Bah, impossible. You just have to approximate. But this is not so. Let's draw ourselves a graph of y= x2, and have a look at a better way of doing things. Take a look at this graph: We have a point P at the position (1,1) and then a point Q at position (1+h, (1+h)2). I initially got confused here: basically, we're looking at a point where x = 1, and then a point a little bit further down the x-axis at x = 1+h, where h is some value (we don't really care all that much what it is). (If you're wondering where (1+h)2 came from, remember the equation we're graphing: y=x2. If x = 1+h, y = (1+h)2.) Let's suppose we're asked to find the gradient at P. We could draw a line between point P and point Q and find its gradient, which will give us a rough approximation of the gradient at point P. We could repeat this over and over, moving Q closer to P every time (and thus getting an answer closer to the real value of the gradient at x = 1). Let's look at the gradient of the line PQ. This is equal to: [math]\frac{y_2 - y_1}{x_2 - x_1} = \frac{(1+h)^2 - 1}{(1+h) - 1} = \frac{(1+h)^2 - 1}{h}[/math] Now just a second. We want to find the limit of this (the answer) as we decrease h to practically nothing. In other words, we want to find the gradient of the line when we move P and Q incredibly close together. So close together that they're actually the same point. That should give us the gradient at x = 1. But we've got a silly h lying around all by itself on the bottom of the equation, meaning that if we just stick h=0 into here, we get something divided by zero - we can't do that. We don't want to just stick a tiny number in for h because that would just be approximating. But wait! There's a way to make h = 0 - which would mean that we're finding the gradient of PQ where P and Q are the same. That would tell us the gradient of the curve at x = 1, which is exactly what we're looking for. So now we have to play around a bit with the fraction, and this is the key operation of this lesson. Make sure you watch very, very carefully and understand each step in the minutest of detail. First of all, notice that (1+h)2 = 1 + 2h + h2. So now we have the gradient equal to: [math]\frac{(1+h)^2 - 1}{h} = \frac{1 + 2h + h^2 - 1}{h} = \frac{2h + h^2}{h} = \frac{h(2 + h)}{h} = 2 + h[/math] Hurrah! Now we have something that we can work with. Notice that if we shrink h to zero as we intended, the gradient of PQ will tend to 2+0 = 2. Or, in other words, the gradient at x = 1 is 2. That's not an approximation, that's the exact answer. To use the appropriate terminology, we have just differentiated the function to find its derivative. So we have a method for finding the exact value of the gradient at a certain point. All those hours of drawing tangents to curves wasted whilst your teacher can work out the answer in his head... Remember, if you need help understanding any of this, you can just ask in our calculus forum.

Haven't you read the thread? The hydrazine is likely frozen in a ball of ice and will easily survive re-entry. I'm not exactly sure why some people worry about debris -- surely if it's going to re-enter, breaking it into bits will leave us loads of small bits that will enter the atmosphere in another month or two. That's not really a long-term problem, except if pieces get blasted into higher orbits.

Please note that the blogs have now been upgraded to the latest version of WordPress, meaning there are a few new features -- tags, for one. (Tags are kinda like categories, but you don't have to create them beforehand, and you can sprinkle them liberally on posts.) If you spot any problems caused by this upgrade please post them here so I can take a look.

Try making a computer calculate who's the most helpful... We have to let members nominate people, put the nominees in polls, and then post the results.

I remember when Dudde had to PM me about spamming too much. ... and look where that got me.

180 seems rather warm. (Very, actually.) This sounds like major hardware failure to me. If you haven't done so already, try to (carefully) remove any dust from inside the case and check to see that all the fans run. (When it's that hot they should be running, I'd think.)

I think this thread won't get any better, so I'll go ahead and lock it for now. Pangloss, we can discuss the rest of this privately.

And both swansont and I made statements that addressed the question of human contribution to global warming.

You still have an opportunity to do something over the summer. Do your research and see if there are any science-oriented summer programs in your area. (You might ask your science teachers if they know of any.) As Lockheed said, it may not be the most crucial thing ever, but it'd be a good experience and it certainly wouldn't hurt.

Have a peek at SpeedFan and see if it can tell you your computer's internal temperatures. (The insides will be surprisingly hot, but numbers like 50C are often indicative of problems.) You may also try checking your computer's memory to see if it's damaged. Use something like Memtest86+ (you can burn it to a CD and tell the computer to boot off of it) to check to see if the memory all works.

Of course it was stupid. Look at the negative response it's generated.

The meaning of life is "anything that dies when you step on it." Oh, sorry, wrong one... From an evolutionary perspective, the purpose of our life is to have children. I'm not philosophical enough to come up with my own meaning.

Your GPA in college is independent of your high school GPA. You'll have a clean slate, as far as I know.

Politics takes about 30 posts to get into. Give it some time.

He asked about intermolecular forces, not intramolecular forces.

Well, think about it. Would hydrogen bonding work in [ce]NH4OH[/ce]? Hydrogen bonding requires a hydrogen atom and an oxygen, nitrogen, or fluorine atom...

Meaning that Suzuki might be threatening jail just to get politicians' hind ends in gear, not because he wants them in jail. It's a way of getting his point across -- an effective one at that. Not "shadow of a doubt" -- "reasonable doubt". If I'm the prosecution I just dig up the part of the paper that says just how likely it is.