Division with variables (I think I'd call this double division)

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Homework Help Overview

The discussion revolves around simplifying a mathematical expression involving variables, specifically a fraction composed of two other fractions over a binomial. The expression in question is ( ( x / y ) - ( 4y / x ) ) / (x + 2y).

Discussion Character

  • Exploratory, Mathematical reasoning, Assumption checking

Approaches and Questions Raised

  • Participants express uncertainty about how to begin simplifying the expression. Some suggest finding a common denominator for the fractions involved, while others question the proper setup and whether simplification is the correct approach.

Discussion Status

There is an ongoing exploration of different methods to simplify the expression. Some participants have attempted to outline steps, such as finding common denominators and considering the difference of squares, but there is no consensus on the correctness of these approaches. Guidance has been offered regarding the importance of not providing complete solutions.

Contextual Notes

Participants emphasize the need for the original poster to engage in the problem-solving process themselves, highlighting the importance of effort before receiving direct solutions. There are also mentions of resources for learning LaTeX, which may be relevant to the formatting of mathematical expressions in the discussion.

wScott
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I don't even know where to start with this question, someone help please.

I don't know how to LaTeX this question so please bare with me:

( ( x / y ) - ( 4y / x ) ) / (x + 2y)

It's two fractions over a binomial.

Hope this isn't to unclear :(
 
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wScott said:
I don't even know where to start with this question, someone help please.

I don't know how to LaTeX this question so please bare with me:

( ( x / y ) - ( 4y / x ) ) / (x + 2y)

It's two fractions over a binomial.

Hope this isn't to unclear :(

Click this for the code to make it:
[tex]\frac{\frac{x}{y} - \frac{4y}{x}}{x + 2y}[/tex]

Now the question on everyone's mind is: what do you actually have to do with this? Simplify it?
 
Last edited:
Yah, sorry about that, and thanks for the LaTeX code. I'm supposed to simplify it but after setting it up like this [tex]\frac{x}{y} - \frac {4y}{x} \times \frac{x + 2y}{1}[/tex] (I think that's proper form anyways) I don't know what else to do.
 
dont know if this is right but it looks good to me

First find the comon denominator in the top fraction

{(x^2-4y^2)/(xy)}/(x+2y)
multiply by the inverse

(x^2-4y^2)/(x^2y+2xy^2)

then diference of squares?

(x+2y)(x-2y)/(xy)(x+2y)

then cancel

(x-2y)/xy


Anyone know a good LaTeX tutorial? I would likke to post more and using LaTeX is just so much prettier :)
 
Last edited:
Gablar16 said:
dont know if this is right but it looks good to me

First find the comon denominator in the top fraction

{(x^2-4y^2)/(xy)}/(x+2y)
multiply by the inverse

(x^2-4y^2)/(x^2y+2xy^2)

then diference of squares?

(x+2y)(x-2y)/(xy)(x+2y)

then cancel

(x-2y)/xy


Anyone know a good LaTeX tutorial? I would likke to post more and using LaTeX is just so much prettier :)
Please, don't show COMPLETE solution. You can guide him, and should let the OP do it him/herself. Showing solutions can be good in some cases, like when the OP has made a great deal of effort trying to solve the problem, but still cannot get the correct answer. But showing solution without any explanation, or without the OP's having shown his/her work, it can be very bad.
You can take some time to readhttps://www.physicsforums.com/showthread.php?t=28.
------------------------
There's a sticky Introducing LaTeX Math Typesetting in the board Math & Science Tutorials (the first board from the top). There are 3 pretty good .PDF files there.
 
VietDao29 said:
Please, don't show COMPLETE solution. You can guide him, and should let the OP do it him/herself. Showing solutions can be good in some cases, like when the OP has made a great deal of effort trying to solve the problem, but still cannot get the correct answer. But showing solution without any explanation, or without the OP's having shown his/her work, it can be very bad.
You can take some time to readhttps://www.physicsforums.com/showthread.php?t=28.
------------------------
There's a sticky Introducing LaTeX Math Typesetting in the board Math & Science Tutorials (the first board from the top). There are 3 pretty good .PDF files there.



You are probably right , sorry about that.
 

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