Search found 56 matches

by Timefly
Tue Sep 11, 2012 10:42 pm UTC
Forum: Mathematics
Topic: Implications of The Riemann Hypothesis
Replies: 2
Views: 2173

Implications of The Riemann Hypothesis

Does the Riemann hypothesis being either true or false imply any specific results about the Riemann Zeta function?
by Timefly
Sun Jul 08, 2012 3:52 pm UTC
Forum: Mathematics
Topic: Your favorite "tricky" integrals?
Replies: 46
Views: 12985

Re: Your favorite "tricky" integrals?

[math]\int \sqrt{1+sin{x}}\,\mathrm{d}x[/math]

The easy way of finding the above antiderivative is quite nice.
by Timefly
Wed Jun 06, 2012 8:06 am UTC
Forum: Individual XKCD Comic Threads
Topic: 1065: "Shoes"
Replies: 107
Views: 41547

Re: 1065: "Shoes"

Running in flip flops is good as it forces you to run on the front of your feet.
by Timefly
Wed May 30, 2012 7:16 am UTC
Forum: Mathematics
Topic: Fitting circles under a curve
Replies: 18
Views: 3669

Re: Fitting circles under a curve

Randommelon wrote:Are you sure that's right, Timefly? I got the intersection of the circle and curve to be approx. x=0.498 and the centre of the circle at x=0.328.


Now you say that, I think I've found a mistake in my working.
by Timefly
Tue May 29, 2012 11:27 pm UTC
Forum: Mathematics
Topic: Fitting circles under a curve
Replies: 18
Views: 3669

Re: Fitting circles under a curve

After an absolutely horrible derivation which I have not the patience to post I've got the x value for the point of intersection between the first circle and the curve e^-x as satisfying the equation (x-a)^3 + (x-a)^2 + (x-a) - a^2 = 0 where a is the x coordinate of the centre of the circle.
by Timefly
Tue May 29, 2012 4:40 pm UTC
Forum: Mathematics
Topic: Probability of consecutive same faces in coin flip
Replies: 7
Views: 2531

Re: Probability of consecutive same faces in coin flip

Assuming that HHHH counts as 2 sets of 2 heads in a row.

Then the chance of getting at least 'a' heads in a row 'b' times in a sample of 'n' trials is given by the function p(a,b,n) = ((n-b)!/n!)*0.5^(ab)
by Timefly
Sat May 19, 2012 9:43 am UTC
Forum: School
Topic: Awesome Student Quotes
Replies: 866
Views: 169507

Re: Awesome Student Quotes

Oh, got another one. We were in history and we had just spent our third lesson on the differences between democracy and dictatorships. Conversation went something like this. Me: I'm telling you, Jamie, we're gonna do another lesson on democracy. Jamie: People aren't that stupid. Me turning around: K...
by Timefly
Sat May 19, 2012 9:23 am UTC
Forum: School
Topic: Awesome Student Quotes
Replies: 866
Views: 169507

Re: Awesome Student Quotes

It was a charity day, so I just happened to be dressed up as a nun. About third period I went into our physics room to talk to the teacher while some younger class was in there. One of the girls in the class goes, "Isn't that racist?"
by Timefly
Fri May 18, 2012 4:53 pm UTC
Forum: Science
Topic: Hilarious Misuses of Quantum Mechanics
Replies: 25
Views: 7434

Re: Hilarious Misuses of Quantum Mechanics

So what don't we see today because we have no knowledge of what to look for? I know what she writes is bullcrap, but this is quite a profound question. Also, finish off the letter to her by saying, "While not agreeing with X/Y/Z, I did watch the Matrix and greatly enjoyed it. Thank you for you...
by Timefly
Wed May 16, 2012 6:20 am UTC
Forum: Mathematics
Topic: Can e^x be thought of as a hyperbola?
Replies: 8
Views: 2911

Re: Can e^x be thought of as a hyperbola?

arbiteroftruth wrote:One way to generalize this to a form that would include exponential(or in this particular case, logarithmic) curves would be to use A+B*x-C, rather than A+B*x-1).


I don't know what you're trying to do here, but the function f(x) = k(1-x^(1/k)) is not equal to the log function for any k.
by Timefly
Fri May 11, 2012 5:41 pm UTC
Forum: Mathematics
Topic: A 'curvy' shape with rational diameter:perimeter
Replies: 17
Views: 3709

Re: A 'curvy' shape with rational diameter:perimeter

Consider a 1 dimensional elastic band in the plane with a rational arc length. By deforming the elastic band continuously the diameter will also change continously. Therefore there must be a 'curvy' shape with rational perimeter and perimeter, depending on your definition of curvy.
by Timefly
Tue Apr 17, 2012 10:14 pm UTC
Forum: Mathematics
Topic: Arccosine (trig function questions)
Replies: 12
Views: 2301

Re: Inverse Trigonometric Functions questions...

G(x) = acos(f(x))
cos(G(x)) = f(x)
by Timefly
Fri Apr 13, 2012 10:01 am UTC
Forum: Mathematics
Topic: Is this right? (improper integral)
Replies: 4
Views: 1665

Re: Is this right? (improper integral)

Your answer is correct. Though the derivation is slightly simpler than that. Just notice that k! = k*(k-1)! and so does your integral, also that your integral has a value of 1 when k = 0. This means you've defined the factorial over the integers. A further proof that the function is meromorphic is r...
by Timefly
Tue Apr 10, 2012 1:46 am UTC
Forum: Mathematics
Topic: Logarithmically growing function with finite limit at infini
Replies: 10
Views: 2711

Re: Logarithmically growing function with finite limit at in

where x is a positive integer? H x is the harmonic series as a function of x, right? Eeyup. But I don't know if the OP would call that logarithmic growth. Because look, I can do this: g(x) = ln(ax) - ln x. This clearly converges to ln a... I suppose. I'm not really convinced such a function exists....
by Timefly
Mon Apr 09, 2012 11:54 pm UTC
Forum: Mathematics
Topic: Logarithmically growing function with finite limit at infini
Replies: 10
Views: 2711

Re: Logarithmically growing function with finite limit at in

I'm thinking something along the lines of log(ax)-H_x
by Timefly
Fri Apr 06, 2012 10:22 am UTC
Forum: Mathematics
Topic: Favorite number sequences?
Replies: 24
Views: 3548

Re: Favorite number sequences?

f(n+1) = (n+2)-f(n), f(0) = 1
by Timefly
Sun Apr 01, 2012 8:16 pm UTC
Forum: Mathematics
Topic: Function converges to square root, but why?
Replies: 7
Views: 3514

Re: Function converges to square root, but why?

korona wrote:
Coding wrote:Neat, I didn't know you could just replace them with x like that. Thanks.

You cannot do that in general. It does not work for general sequences and it is just coincidence that it works in this case.

Assuming the sequence is convergent, then it's perfectly reasonable.
by Timefly
Thu Mar 29, 2012 4:04 pm UTC
Forum: Mathematics
Topic: Being Fast At Calculation
Replies: 14
Views: 2715

Re: Being Fast At Calculation

Thanks everyone. I guess practice it is.
by Timefly
Thu Mar 29, 2012 4:03 pm UTC
Forum: Science
Topic: Tulpas
Replies: 4
Views: 1706

Tulpas

So, the following has been popping up in various corners of the internet recently. http://louderthanthunder.net/tulpa.html There are detailed guides as to what Tulpas are at the top of the page on the link provided, but a basic run down is something like; creating a Tulpa is when, through the persis...
by Timefly
Thu Mar 22, 2012 11:00 pm UTC
Forum: Mathematics
Topic: Being Fast At Calculation
Replies: 14
Views: 2715

Re: Being Fast At Calculation

If you're slow at calculation, you can do what anyone has to do to become faster: practice. Identify what's taking you a long time, make up some problems similar to those, and practice solving them quickly and without errors. i suppose I just need to knuckle down and get on with things. Thanks. Rem...
by Timefly
Thu Mar 22, 2012 4:01 pm UTC
Forum: Mathematics
Topic: Being Fast At Calculation
Replies: 14
Views: 2715

Re: Being Fast At Calculation

Currently I'm working on linear differential equations. I always get slowed down in things like equating coefficients to find a particular integral. Arithmetic is generally fine as I'm quite handy with a calculator. It's just highly mechanical things. Edit: Here's an example of the kind of thing we'...
by Timefly
Thu Mar 22, 2012 11:55 am UTC
Forum: Mathematics
Topic: Being Fast At Calculation
Replies: 14
Views: 2715

Being Fast At Calculation

I have a problem, I'm slow at calculation. In my maths courses I can understand everything I need to, I can do all the calculation I need to, I just can't do it as quickly as I need to. This makes exams particularly hard for me as my work becomes a rushed mess. So does anyone know any good ways of b...
by Timefly
Tue Mar 20, 2012 6:46 pm UTC
Forum: Mathematics
Topic: Infinity paradox? Help
Replies: 54
Views: 8078

Re: Infinity paradox? Help

Stuff... I think what he's getting is the natural numbers as a set having the property such that N r = r Then, from this, reasoning that the last member in N is given by N INFINITY because every index has a corresponding member with the property already stated and there must be an 'upper bound'. Th...
by Timefly
Fri Mar 02, 2012 9:18 pm UTC
Forum: Mathematics
Topic: Favorite math jokes
Replies: 1452
Views: 457493

Re: Favorite math jokes

Chat up line:

Baby, if I were to rearrange the alphabet there'd only be 2x25! permutations because I'd always keep 'u' and 'i' together.
by Timefly
Tue Feb 28, 2012 4:57 pm UTC
Forum: Mathematics
Topic: Funny mathematical terms and statements
Replies: 21
Views: 7407

Re: Funny mathematical terms and statements

The statement "almost all".
by Timefly
Sun Feb 26, 2012 4:05 pm UTC
Forum: Mathematics
Topic: Erdos Conjecture
Replies: 18
Views: 6900

Re: Erdos Conjecture

Alright. Never mind.
by Timefly
Sun Feb 26, 2012 2:34 pm UTC
Forum: Mathematics
Topic: Erdos Conjecture
Replies: 18
Views: 6900

Re: Erdos Conjecture

I'm not sure there's any basis for the following statement... If the conjecture is false, then there exists a sequence with no arithmetic progressions of length 3 such that the sum of the reciprocals of the series diverges. It could be that in every sum of the reciprocals of a series that diverges t...
by Timefly
Thu Feb 02, 2012 5:55 pm UTC
Forum: Mathematics
Topic: Temporal distortion, geodesics(?), and My Little Pony
Replies: 24
Views: 2768

Re: Temporal distortion, geodesics(?), and My Little Pony

I fail to see what this has to do with 'My Little Pony'.
by Timefly
Tue Jan 31, 2012 4:21 pm UTC
Forum: Fictional Science
Topic: If you could change the laws of physics...
Replies: 50
Views: 23894

Re: If you could change the laws of physics...

I'd lower the speed of light to 200mph.
by Timefly
Sat Jan 21, 2012 3:53 pm UTC
Forum: Mathematics
Topic: Obscure branches of math?
Replies: 67
Views: 14967

Re: Obscure branches of math?

doogly wrote:The fact that you were not taught the applications for those topics says very little about the topics themselves, and more about the narrowness of the presentation.


I suppose that's fair, but the whole course feels more like a primer for a degree in maths than anything else.
by Timefly
Fri Jan 20, 2012 9:01 pm UTC
Forum: Mathematics
Topic: Obscure branches of math?
Replies: 67
Views: 14967

Re: Obscure branches of math?

Replying to people saying that Pure Math is not taught in the UK. I'm an A level maths student and in our 'Core' modules we generally cover what might be though of as 'Pure' mathematics; being things like Calculus, functions, iterative formulae, further trigonometry etc... For real pure mathematics ...
by Timefly
Sat Dec 10, 2011 6:02 pm UTC
Forum: Mathematics
Topic: Logical Converses
Replies: 3
Views: 1235

Re: Logical Converses

Thanks, this is really useful. I think I just realized how I might be able to show that the conjecture relies on the equations existing. me thinks this shall not be simple though.
by Timefly
Sat Dec 10, 2011 4:33 pm UTC
Forum: Mathematics
Topic: Logical Converses
Replies: 3
Views: 1235

Logical Converses

Given that I have a conjecture and if that conjecture were to be proved true it would show that a certain set of equations could not exist.
If I could prove that said set of equations didn't exist by other means, could I then use that result yo somehow show that the conjecture is true?
by Timefly
Mon Oct 31, 2011 4:29 pm UTC
Forum: Mathematics
Topic: Why aren't the rationals more numerous than the integers?
Replies: 34
Views: 4686

Re: Why aren't the rationals more numerous than the integers

Arrange the rationals as so... 1/1 1/2 1/3 1/4 1/5... 2/1 2/2 2/3 2/4 2/5... 3/1 3/2 3/3 3/4 3/5... 4/1 4/2 4/3 4/4 4/5... 5/1 5/2 5/3 5/4 5/5... . . . . . . . . . . . . . . . Now start at the top left hand corner of the grid and begin to draw a line snaking through the grid. So the line starts at 1...
by Timefly
Wed Oct 26, 2011 10:25 pm UTC
Forum: Mathematics
Topic: What do you think the most underrated area of math is?
Replies: 13
Views: 3512

Re: What do you think the most underrated area of math is?

Baseball dates back to Euclid.

- A bat can be swung between any two points.
by Timefly
Thu Oct 13, 2011 10:51 pm UTC
Forum: Mathematics
Topic: The Tau Manifesto
Replies: 165
Views: 41597

Re: The Tau Manifesto

May I just say...

WHO CARES?

Seriously, maths has more to worry about than your silly notation for circle constants, could we maybe be having a look at function notation if we're going to get into notation arguments.
by Timefly
Wed Oct 05, 2011 3:25 pm UTC
Forum: Mathematics
Topic: Half derivatives
Replies: 1
Views: 800

Half derivatives

Why do there seem to be two consistent half derivatives for ecx?
One being c0.5ecx and the other being when you differentiate term by term the taylor polynomial of it.
by Timefly
Wed Sep 21, 2011 4:45 pm UTC
Forum: Mathematics
Topic: Generators of Infinite Groups
Replies: 5
Views: 966

Generators of Infinite Groups

Is there any generalized method of finding out if an infinite group has a generator.

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