Could somebody explain how we get the 2nd equation from the 1st?

1) 3 (x − 3)^3 (x + 5)^2 − 3 (x + 5)^3 (x − 3)^2

2) 3 (x − 3)^2 (x + 5)^2 [(x − 3) − (x + 5)]

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- Mar 31st 2010, 07:02 PMp75213Rewriting an equation.
Could somebody explain how we get the 2nd equation from the 1st?

1) 3 (x − 3)^3 (x + 5)^2 − 3 (x + 5)^3 (x − 3)^2

2) 3 (x − 3)^2 (x + 5)^2 [(x − 3) − (x + 5)] - Mar 31st 2010, 07:27 PMWilmer
- Mar 31st 2010, 07:47 PMp75213
Sorry. Still don't get it. Wouldn't 3a^2b^2(a-b) expand into 3a^3b^2-3a^2b^3. Seems like I am missing something here.

- Mar 31st 2010, 07:47 PMdjsnare

I think they just factored out a common term:

http://www.djsnare.ca/equation2.jpg

If you were to multiply it out, you should get back to the first expression. - Mar 31st 2010, 08:00 PMWilmer
- Mar 31st 2010, 08:01 PMp75213
Yep - that's it. Many thanks.