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Thanks bobby ... yes and yes: ±√(2x^2+c) − x is what I get now.

**MathsIsFun**- Replies: 4

And another in the Diff Eq series: Homogeneous Differential Equations

The main weakness in this page is no explanation of why they are "Homogeneous". I played with linking **f(zx,zy) = z^n f(x,y)** to **dy/dx=F(x/y)** form but failed. If anyone knows a user-friendly way of explaining why "Homogeneous" that would be nice.

Comments, suggestions and error checking welcome.

Les is going to make some questions (with worked answers) for the bottom of the page.

Makes sense to me, I will put ±, thanks.

Have made changes to the page Separation of Variables

Is it looking better now? Did I miss any of your points in the rewrite?

**MathsIsFun**- Replies: 4

Continuing on with the series on Differential Equations: Solution of First Order Linear Differential Equations

Credit also goes to Les Bill Gates, a very capable mathematics teacher, for these pages.

I have been experimenting with a new way of formatting dy/dx etc, so if you notice any formatting issues could you screen print and post them so I can see (but try Refresh first).

I would value any feedback, ideas for improvement, and error checking!

Yes please do!

**MathsIsFun**- Replies: 11

Just finished off this Diff Eq page: Separation of Variables

It would be really nice if everyone could check it for mistakes before I make it live on the website.

Comments and suggestions welcome too.

I have updated the definition to this:

I wrote:

Coefficient

A number used to multiply a variable.

Example: 6z means 6 times z, and "z" is a variable, so 6 is a coefficient.

Sometimes a letter stands in for the number.

Example: In ax² + bx + c, "x" is a variable, and "a" and "b" are coefficients.

Let me know if you feel it can be improved.

ShivamS wrote:

However, we can't say that c is a coefficient in ax^2 + bx + c, but we can say it is in ax^2 + bx + cx^0.

That makes sense.

What does everyone think about that?

OK, this is the new wording (so far), improvements welcome!

"The number (or other fixed value) part of a term, such as the 4 in 4y

A constant can also be though of as a coefficient. In ax² + bx + c, a, b and c are coefficients."

Yes, it seems there is not consensus.

I do feel that having a constant also be a coefficient is more elegant (like a square being a rectangle).

How about

"The number (or other fixed value) part of a term."

With an example.

Yes, we normally draw a distinction between coefficient and constant, but then a constant is also a coefficient. A bit like a square is a rectangle.

How about

A number (or other fixed value) used to multiply in algebra.

So, what is a good and easy to understand (for adults and children) definition of coefficient ... ?

**MathsIsFun**- Replies: 46

On the website I define a coefficient as "A number used to multiply a variable"

So, in

3 and 7 are coefficients and 2 is a constant. But is 2 also a coefficient?

How about in

Are a, b and c all coefficients?

(I want the simplest accurate definition.)

Got a good one have you?

Thanks Guys!

bobbym wrote:

I thought the degree of an ODE was the power that the highest derivative was raised to.

Yes, will fix.

**MathsIsFun**- Replies: 8

A new page: Differential Equations - Introduction

Could you please go over this with a fine-tooth comb and find any inaccuracies. In my attempt to simplify I may have gone too far.

Suggestions and comments also welcome.

Length of robot?

Hmm... the technicians would not likely fall into the "50 mph" trap, so we may assume their answer is technically correct.

So "stupid guy" must be including some other fact.

I see

Bobbym is in, yay!

Default theme is now Air, and I upgraded 'SleekBlue' users to it.

Forum is currently not accepting new members or Guest posts as we got a lot of spam.

I will work on fixes to Search, Spam, etc as time goes by (days most likely).

Keep posting!

Hmm... is that a feature or a bug

Thank you, will look into it.

I am going to have a rest now as I have been working on this all day. Look forward to lots of things to tackle when I get back.