HELP! I need help Multiplying Polynominals!

[music_and_words]

Ok, so this is really confusing me. I understand how to use the distrubutive property, but when they ask me to Foil, I get totaly lost. Here's an example from the book I'm working in;
3(y-1)2 -2(2y-1)2

If ANYONE has any idea what I'm talking about and can help, I'd be really, really greatfull. Thanks

 

[Loren]

FOIL stands for First, Outer, Inner, Last.
Given two binomials, say, (a + b)(c + d), using FOIL, proceed as follows (paying close attention to signs):

1. Multiply the two FIRST terms getting >>> ac
2. Multiply the OUTER terms getting >>> ad
3. Multiply the INNER terms getting >>> bc
4. Multiply the LAST terms getting >>> bd
5. Finally add these getting >>> ac + ad + bc + bd.
6. Combine like terms if possible.

In your case the form is 3a[sup:168ytjf8]2[/sup:168ytjf8] - 2b[sup:168ytjf8]2[/sup:168ytjf8].

3(y-1)[sup:168ytjf8]2[/sup:168ytjf8] -2(2y-1)[sup:168ytjf8]2[/sup:168ytjf8]
Use FOIL on the first term and then again on the second term (both in blue), then combine like terms. It will look like this.

3(y-1)(y-1) - 2(2y-1)(2y-1) = ??? etc.

 

[Deleted member 4993]

Do you mean your problem looks like:

\(\displaystyle 3\cdot (y-1)^2 -2\cdot (2y-1)^2\)

then

\(\displaystyle 3\cdot (y-1) \cdot (y-1) -2\cdot (2y-1) \cdot (2y-1)\)

then continue....

Read:

http://www.purplemath.com/modules/polymult2.htm

Specifically, read about when FOIL does not work. I, never learned FOIL - and I have taken graduate level courses in applied math (engineering).