Discussion about math, puzzles, games and fun.   Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫  π  -¹ ² ³ °

You are not logged in.

#1 2006-02-27 11:06:59

Patrick
Real Member
Registered: 2006-02-24
Posts: 1,005

Equation of a Straight Line

Would just like to point out that in Denmark we use y=ax+b

Support MathsIsFun.com by clicking on the banners.
What music do I listen to? Clicky click

Offline

#2 2006-02-27 11:30:02

Ricky
Moderator
Registered: 2005-12-04
Posts: 3,791

Re: Equation of a Straight Line

In Virginia, we use:

Where p is a prime number.

Last edited by Ricky (2006-02-28 09:05:17)

"In the real world, this would be a problem.  But in mathematics, we can just define a place where this problem doesn't exist.  So we'll go ahead and do that now..."

Offline

#3 2006-02-27 11:41:29

MathsIsFun
Registered: 2005-01-21
Posts: 7,659

Re: Equation of a Straight Line

Ha ha!

Tak for det, Patrick!

"The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  - Leon M. Lederman

Offline

#4 2006-02-27 19:13:04

krassi_holmz
Real Member
Registered: 2005-12-02
Posts: 1,905

Re: Equation of a Straight Line

Cool, ricky where did you get this?

IPBLE:  Increasing Performance By Lowering Expectations.

Offline

#5 2006-02-28 09:04:48

Ricky
Moderator
Registered: 2005-12-04
Posts: 3,791

Re: Equation of a Straight Line

I made it.  Just simpily and you should get:

y/(ab) = x/b + 1/a, which of course is y = ax + b

"In the real world, this would be a problem.  But in mathematics, we can just define a place where this problem doesn't exist.  So we'll go ahead and do that now..."

Offline

#6 2006-02-28 11:03:29

Patrick
Real Member
Registered: 2006-02-24
Posts: 1,005

Re: Equation of a Straight Line

hehe, ricky - The reason I wrote this, was because of the request at the bottom of this page http://www.mathsisfun.com/equation_of_line.html

Support MathsIsFun.com by clicking on the banners.
What music do I listen to? Clicky click

Offline

#7 2006-02-28 11:25:06

Ricky
Moderator
Registered: 2005-12-04
Posts: 3,791

Re: Equation of a Straight Line

Ah, ok, didn't know about that Patrick.

Well Mathisfun?  Aren't you going to put mine on that page as well?

"In the real world, this would be a problem.  But in mathematics, we can just define a place where this problem doesn't exist.  So we'll go ahead and do that now..."

Offline

#8 2006-02-28 19:57:42

krassi_holmz
Real Member
Registered: 2005-12-02
Posts: 1,905

Re: Equation of a Straight Line

Ya, now when i"m looking this MONSTER equation it looks loke very simple.
Pretty good example how BEAUTIFUL maths can be.

IPBLE:  Increasing Performance By Lowering Expectations.

Offline

#9 2006-02-28 21:31:46

MathsIsFun
Registered: 2005-01-21
Posts: 7,659

Re: Equation of a Straight Line

Ricky wrote:

Well Mathisfun?  Aren't you going to put mine on that page as well?

Do you think it will fit?

"The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  - Leon M. Lederman

Offline

#10 2006-03-01 17:38:57

krassi_holmz
Real Member
Registered: 2005-12-02
Posts: 1,905

Re: Equation of a Straight Line

If it don't you can simplify it....
A little...
(You can call this "Ricky's approach")

IPBLE:  Increasing Performance By Lowering Expectations.

Offline

#11 2006-08-05 01:53:42

nikconsult
Member
Registered: 2006-08-04
Posts: 48

Re: Equation of a Straight Line

In Malaysia we use y=mx+c

Offline

#12 2006-08-05 10:31:00

Zhylliolom
Real Member
Registered: 2005-09-05
Posts: 412

Re: Equation of a Straight Line

I've never heard of any of the equations in this thread. In my studies I have always used

where ζ is Riemann's zeta function, Γ(x) is the gamma function, ∇ is the del operator, L[sup]-1[/sup] denotes the inverse Laplace transform, T[sub]n[/sub] is the nth Chebyshev polynomial of the first kind, C is a simple closed curve bounding a region having z = a as an interior point, σ[sub]0[/sub][sup]m[/sup] is a simplex of an oriented simplicial complex and [σ[sup]m[/sup], σ[sup]m - 1[/sup]] is an incidence number, S is a compact, orientable, differentiable k-dimensional manifold with boundary in E[sup]n[/sup] and ω is a (k - 1)-form in E[sup]n[/sup], defined, and C[sup]1[/sup] at all points of S, and η(x) is Dirichlet's eta function.

(Sorry for stealing your joke, Ricky. )

Last edited by Zhylliolom (2006-08-06 14:11:03)

Offline

#13 2006-08-05 10:40:14

MathsIsFun
Registered: 2005-01-21
Posts: 7,659

Re: Equation of a Straight Line

Ha! That's only the simplified version!

nikconsult: updated page, mentioned Malaysia: Equation of a Straight Line

"The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  - Leon M. Lederman

Offline

#14 2006-08-05 12:11:58

Ricky
Moderator
Registered: 2005-12-04
Posts: 3,791

Re: Equation of a Straight Line

(Sorry for stealing your joke, Ricky. )

Now your going to force me to go through and check the entire thing.  And did I see a surface integral in there?  I had a calc professor who said, "You should only think one thing whenever you see a surface integral and that's, 'AHHHHH!!!!'"

"In the real world, this would be a problem.  But in mathematics, we can just define a place where this problem doesn't exist.  So we'll go ahead and do that now..."

Offline

#15 2006-08-05 12:28:54

Zhylliolom
Real Member
Registered: 2005-09-05
Posts: 412

Re: Equation of a Straight Line

Making sure everything checks out would be a good exercise. After solving it, you'll realize that I made it rather simple... I should have made things crazier. Here are some things you can look into if you really want to see how it simplifies and get stuck: Elliptic integrals, obscure trigonometric identities, the Bromwich integral, obscure(and maybe somewhat non-obscure) infinite sums and products, definitions of obscure constants, contour integrals, simplicial homology theory, differential geometry, and integration of differential forms, just to name a few topics.

Offline

#16 2006-08-06 05:16:24

luca-deltodesco
Member
Registered: 2006-05-05
Posts: 1,470

Re: Equation of a Straight Line

in england, we tend to use y = mx + c

The Beginning Of All Things To End.
The End Of All Things To Come.

Offline

#17 2006-08-06 13:01:23

Ricky
Moderator
Registered: 2005-12-04
Posts: 3,791

Re: Equation of a Straight Line

is C², right Zylliolom?

"In the real world, this would be a problem.  But in mathematics, we can just define a place where this problem doesn't exist.  So we'll go ahead and do that now..."

Offline

#18 2006-08-06 13:19:22

Ricky
Moderator
Registered: 2005-12-04
Posts: 3,791

Re: Equation of a Straight Line

Isn't that supposed to be:

No?  Assumming it is, I got:

"In the real world, this would be a problem.  But in mathematics, we can just define a place where this problem doesn't exist.  So we'll go ahead and do that now..."

Offline

#19 2006-08-06 13:23:05

Zhylliolom
Real Member
Registered: 2005-09-05
Posts: 412

Re: Equation of a Straight Line

No, A is an arbitrary vector. Just think about what the divergence of the curl is. I posted the formula for it in the Vector Formulas thread, but it should only take a moment to calculate it yourself.

Oh man, it's not letting me simply post "curl" again... and you're correct on the integral, I'll fix that typo right now.

Offline

#20 2006-08-06 13:25:54

Ricky
Moderator
Registered: 2005-12-04
Posts: 3,791

Re: Equation of a Straight Line

My book has that the divergence of a cur1 for any C^2 vector field F is 0... are you saying that C^2 is not needed?

And I got the same error when using cur1 as you did, hence the 1.

"In the real world, this would be a problem.  But in mathematics, we can just define a place where this problem doesn't exist.  So we'll go ahead and do that now..."

Offline

#21 2006-08-06 13:27:52

Zhylliolom
Real Member
Registered: 2005-09-05
Posts: 412

Re: Equation of a Straight Line

That's good so far.

Offline

#22 2006-08-06 13:30:15

Ricky
Moderator
Registered: 2005-12-04
Posts: 3,791

Re: Equation of a Straight Line

If anyone wants to jump in here and help me out (besides Zhylliolom), feel free.

Of course, correct me if you see any mistakes.

"In the real world, this would be a problem.  But in mathematics, we can just define a place where this problem doesn't exist.  So we'll go ahead and do that now..."

Offline

#23 2006-08-06 13:40:28

Zhylliolom
Real Member
Registered: 2005-09-05
Posts: 412

Re: Equation of a Straight Line

Wow, I don't know why I thought you meant C[sup]2[/sup] (as in some quantity or some vector) instead of C[sup]2[/sup].

Offline

#24 2006-08-06 14:14:01

Ricky
Moderator
Registered: 2005-12-04
Posts: 3,791

Re: Equation of a Straight Line

Cool integral.  Is there a special name for it?

"In the real world, this would be a problem.  But in mathematics, we can just define a place where this problem doesn't exist.  So we'll go ahead and do that now..."

Offline

#25 2006-08-06 14:27:52

Zhylliolom
Real Member
Registered: 2005-09-05
Posts: 412

Re: Equation of a Straight Line

It's a special case of the polylogarithm known as the dilogarithm, this specific case is -Li[sub]2[/sub](1). Note that Li[sub]s[/sub](1) = ζ(s).

Last edited by Zhylliolom (2006-08-06 15:08:59)

Offline