Math question - Polynomials

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Thenior
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Math question - Polynomials

Post by Thenior »

Hey guys and gals,

Have a quick math question.

I have this math problem:

| x^-2y | ^-2
|x^-3y^5|

Or if you prefer to have it written out correctly:

Code: Select all

((x^-2y)/(x-3y^5))^-2
Here is the conclusion I came to:

1) Distribute

Code: Select all

^-2
this would equal:

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x^4 y^-2 / x^6 y^-10
2) Flip negative exponents. This would equal:

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x^4 y^10 / x^6 y^2
3) Subtract denominator exponents from numerator. This would equal:

Code: Select all

y^8 / x^2
Is my logic sound? This was on some homework I have, and none of the text went over this specific type of problem.
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fliptw
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Re: Math question - Polynomials

Post by fliptw »

is it x^2-2y or x^(-2y)?

note: (x+1)^2 != x^2+1
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snoopy
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Re: Math question - Polynomials

Post by snoopy »

If your original equation is this:
math.JPG
math.JPG (2.04 KiB) Viewed 623 times
I think you did it correctly. Next time, use "*" signs and more parentheses to denote multiplication and what's being raised to what power, otherwise, your equation could read like this, which is a different beast:
math2.JPG
math2.JPG (1.99 KiB) Viewed 623 times
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Thenior
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Re: Math question - Polynomials

Post by Thenior »

Sorry snoopy - thanks for the info and help!
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snoopy
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Re: Math question - Polynomials

Post by snoopy »

It's all good. When/if you get into using computer programs to solve stuff for you, you can get messed up. I'm usually really crazy about parenthesis in excel, just to make sure that it performs the correct operations on the correct items.
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Burlyman
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Re: Math question - Polynomials

Post by Burlyman »

These are rational functions, not polynomials. Just sayin'. :P
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Top Gun
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Re: Math question - Polynomials

Post by Top Gun »

Um...they're rational polynomials, chief. :P
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Re: Math question - Polynomials

Post by Foil »

Yep, they're simply rational polynomial expressions at this point.
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