Factor expression A so that it looks like expression B

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The discussion focuses on factoring the expression -a^2b + ab^2 + a^2c - b^2c - ac^2 + bc^2 into the form -(a-b)(a-c)(b-c). The user initially struggles with the factorization process but makes progress by rearranging the terms. They express the equation in a different format, leading to a clearer path for factoring. The conversation highlights the importance of rearranging terms to facilitate the factoring process. Ultimately, the user expresses gratitude for the assistance received in solving the problem.
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Homework Statement


This question stems from this one: https://www.physicsforums.com/showthread.php?t=642712

I think I know how to solve it now. The only problem is I have to show how to factor this expression into the form WolframAlpha shows.

-a^2 b + a b^2 + a^2 c - b^2 c - a c^2 + b c^2 → -(a-b)(a-c)(b-c)

Homework Equations


The Attempt at a Solution



I did this but then I don't know how to proceed.

ab(b-a)+ac(a-c)+bc(c-b)

Please help. Thanks
 
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By rearranging it like so:
−a^2b+ab^2+a^2c−b^2c−ac^2+bc^2 \rightarrow −a^2b+a^2c+ab^2−ac^2−b^2c+bc^2
 
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You're a genius! Thank you. :)
 
I tried to combine those 2 formulas but it didn't work. I tried using another case where there are 2 red balls and 2 blue balls only so when combining the formula I got ##\frac{(4-1)!}{2!2!}=\frac{3}{2}## which does not make sense. Is there any formula to calculate cyclic permutation of identical objects or I have to do it by listing all the possibilities? Thanks
Since ##px^9+q## is the factor, then ##x^9=\frac{-q}{p}## will be one of the roots. Let ##f(x)=27x^{18}+bx^9+70##, then: $$27\left(\frac{-q}{p}\right)^2+b\left(\frac{-q}{p}\right)+70=0$$ $$b=27 \frac{q}{p}+70 \frac{p}{q}$$ $$b=\frac{27q^2+70p^2}{pq}$$ From this expression, it looks like there is no greatest value of ##b## because increasing the value of ##p## and ##q## will also increase the value of ##b##. How to find the greatest value of ##b##? Thanks
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