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

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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?
 
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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 [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 :)
 
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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.
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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.