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## #1 Re: Maths Is Fun - Suggestions and Comments » Spelling? » 2010-02-27 15:41:01

Got it right for me.

Your browser language setting is en-US

So these are the spellings we will use:

Math, meter, liter, color, organization.

## #2 Re: Maths Is Fun - Suggestions and Comments » Systems of Linear Equations » 2010-02-11 13:35:51

Awesome page, really great stuff!

I just noticed a few things:

Small typo for "iseems":
In this case it iseems easiest to set them equal to each other:

And the solve by substitution method for 3x3 under the section "Now replace "z" with "3 - y" in the other equation:" the 3-y is not aligned correctly. 3-y is not on one line but the y goes underneath.

## #3 Re: Help Me ! » My SQL? » 2010-01-20 15:08:51

MIF is running fine for me.

## #4 Re: Maths Is Fun - Suggestions and Comments » The Rule of Signs » 2009-12-17 15:35:31

The page's looking good.

## #5 Re: Maths Is Fun - Suggestions and Comments » Fundamental Theorem of Algebra » 2009-12-17 02:33:09

"A "root" (or "zero") is where the function crosses the x-axis "

Maybe this should be reworded to 'A "root" (or "zero") is a value where the function equals 0' because the function doesn't have to cross the x-axis, but it could be tangent with it. And then show a example: f(3) = 3^2 + 4(3) - 21 = 0

## #6 Re: Maths Is Fun - Suggestions and Comments » Fundamental Theorem of Algebra » 2009-12-16 12:48:10

Great job! For the multiplicity section I would suggest adding that if the multiplicity of a factor is even then the graph will be tangent with the x-axis at those roots and if odd the graph will cross the x-axis at those roots.

## #7 Re: Maths Is Fun - Suggestions and Comments » Solving Polynomials » 2009-12-11 13:20:20

Page looks great!

## #8 Re: Help Me ! » How is the conic section discriminant derived? » 2009-12-11 08:38:22

Yup, I was just curious. Thanks for your feedback. I think I figured it out, I'm teaching myself this stuff. I had a pretty crummy math education. Teachers weren't that great. Anyways, from your reply on my other question "How to derive other equations from the general conic section equation?" I'm assuming that Bxy = 0, Cy2 = 0, and Ey = 0 for the general conic section equation: Ax2 + Bxy + Cy2 + Dx + Ey + F = 0 and what's left is a quadratic. From that I can get the discriminant.

## #9 Re: Help Me ! » How is the conic section discriminant derived? » 2009-12-08 07:47:35

Hi Mikau, thanks for your answer, but what I'm trying to say is how was the formula B^2 - 4AC derived from Ax^2 + Bxy + Cy^2 + Dx + Ey + F = 0? Where did B^2 - 4AC come from?

## #10 Re: Help Me ! » How to derive other equations from the general conic section equation? » 2009-12-08 07:44:32

Thanks for clearing that up for me!

## #11 Help Me ! » How to derive other equations from the general conic section equation? » 2009-12-07 16:50:17

ccmint
Replies: 2

I've just read the Conic Sections page and at the bottom it says that the general equation can be used to create equations for the circle, ellipse, parabola and hyperbola. How can I create those equations? BTW, I've search all of Google and couldn't find anything.

Thanks!

## #12 Help Me ! » How is the conic section discriminant derived? » 2009-12-07 07:57:11

ccmint
Replies: 4

Hi,

How can I derived the conic section discriminant from the general equation Ax^2 + Bxy + Cy^2 + Dx + Ey + F = 0

The book I'm reading says that it's taken from A,B,C. I don't see how Ax^2 + Bxy + Cy^2 can be turned into b^2-4ac. I know that Ax^2 + Bx + C can be used to get the discriminant from learning about quadratics, but like I said the book says it uses A,B,C. My best guess is that they meant it's derived from Ax^2 + Dx + F. I'm not sure but I think I'm interpreting the text wrong. Can someone please clear this up for me? Thanks.

Thanks, Bobby.

## #14 Re: Help Me ! » Why do we find the zeros of a function? » 2009-11-03 05:47:54

If I understand this correctly, we graph an equation, where it intersects the x-axis is the answer to that equation. And the answer is called the root or the zero of the equation.

## #15 Help Me ! » Why do we find the zeros of a function? » 2009-11-03 03:31:48

ccmint
Replies: 6

I know it's to see where the function crosses the x-axis, but what does this actually mean and how is this useful? How is this useful in a real world example?

Thanks!
John

## #16 Re: Maths Is Fun - Suggestions and Comments » Mathematical Models » 2009-10-27 05:39:34

Ok, Thanks Bobby.

## #17 Re: Maths Is Fun - Suggestions and Comments » Mathematical Models » 2009-10-27 05:20:12

The page looks great. I just have one question. How did you figure out the minimum (0.22, 0.17)?

## #18 Re: Help Me ! » Need help with factoring. » 2009-10-26 05:04:35

Thanks Bobby and Luca. It all makes sense now.

Have a great day, John

## #19 Re: Help Me ! » Need help with factoring. » 2009-10-26 02:48:59

Thanks Luca for your response, but I'm still confused to how (x+1)(x^2-5x+5) was factored out from x^3-4x^2+5.

Is (x+1)(x^2+bx+x) a identity that has to be recognized through x^3-4x^2+5?

## #20 Help Me ! » Need help with factoring. » 2009-10-25 18:10:26

ccmint
Replies: 5

I saw this problem on sosmath.com - http://www.sosmath.com/algebra/pfrac/pfrac.html

x^3 - 4x^2 + 5

and it's suppose to factor out to (x+1)(x^2-5x+5) and I've been sitting here trying to get it to that form but I only end up with (x^2+5)(x-4). Can someone please shed some light to how this can be factored out to (x+1)(x^2-5x+5). Thanks!

## #21 Re: Maths Is Fun - Suggestions and Comments » And The Subject Is ... » 2009-10-25 16:50:17

I agree I like the name Advanced Algebra.

## #22 Introductions » Hi all - and I have a question. :) » 2009-10-11 13:18:50

ccmint
Replies: 3

So, I've survived all my math classes from elementary school through college (BS), but I've gotten through without understanding why I'm learning what I was being taught. I felt lost and still feel lost. I'm finding it difficult seeing the whole picture. I'm looking for a chart, map or list of some kind that shows the major areas of math and how they are related to each other. I think if I have something visual to look at I will have a better sense of how everything fits together. Also, it would be helpful if it described where that area of mathematics is applied. Do you know where I can find this? Or can you help me out and make one. Thanks! John