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

AI Thread Summary
The discussion revolves around simplifying the expression ((x/y) - (4y/x)) / (x + 2y). Participants suggest finding a common denominator for the top fraction and then multiplying by the inverse of the denominator. The simplification process involves recognizing the difference of squares and canceling terms appropriately. There is also a request for guidance on using LaTeX for better presentation of mathematical expressions. Overall, the focus is on providing support for the simplification process while encouraging the original poster to engage with the problem.
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:
\frac{\frac{x}{y} - \frac{4y}{x}}{x + 2y}

Now the question on everyone's mind is: what do you actually have to do with this? Simplify it?
 
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Yah, sorry about that, and thanks for the LaTeX code. I'm supposed to simplify it but after setting it up like this \frac{x}{y} - \frac {4y}{x} \times \frac{x + 2y}{1} (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 :)
 
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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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