Talk:FOIL rule

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Mathematics grading:	Stub Class	Low Importance	Field: Basics

[edit] Frowned upon?

The article says:

It is commonly taught, but is often frowned upon because the method does not work for higher order polynomials, and thus instead of actually teaching a general method, it is an example of learning by rules instead of concepts.

Hmm. I don't know about this. While the exact method may not be applicable, it is easily extended to polynomials with more terms. Besides, how else is one supposed to learn to muliply polynomials? What could this other "general method" be that would be useful to beginning algebra students? - dcljr (talk) 4 July 2005 10:10 (UTC)

Well that is a very common sentiment. I forgot to mark down any source that mentions it, but it is certainly common. I'll see what I can do to dig one up. - Taxman ^Talk July 5, 2005 15:26 (UTC)

I definitely agree with the article. FOIL avoids any kind of reasoning or understanding of what's going on. Extending it is confusing, because then it's no longer FOIL. To teach a general method without using FOIL, you could, for example, first explain why .

Then show why . The general principle follows. TMott 22:01, 2 September 2005 (UTC)

Okay, now that I've actually started teaching an algebra class, I understand: the "general method" is simply distributing, and is basically what TMott is talking about (and what I meant when I said FOILing is "easily extended"). Although... I guess "true" distributing requires two separate steps where you first distribute one polynomial (in parentheses) over the terms of the other, then distribute again to get rid of the parentheses (hence the term "double distributive property" mentioned in the article). What I was talking about is essentially a shortcut where you see the pattern and skip the first distributing step. TMott, it seems to me you were really talking about the same thing I was. BTW, a different way of looking at it, although completely equivalent of course, is called the "vertical format" and works the way most people learned to multiply numbers bigger than 10 on paper, by first lining them up vertically. - dcljr (talk) 06:51, 3 September 2005 (UTC)

Yeah, it seems you were talking about the same thing, but missing the part about it not being FOIL anymore. But the phrase could certainly use some attribution to a reputable source, and I haven't been able to locate one. Is there a well regarded textbook regarding teaching algrebra you know of? I may be able to go to the university bookstore and look for one. Also, I couldn't find any article that actually explains polynomial multiplication. Polynomial certainly doesn't, though we do have polynomial long division. Do you guys mind creating the article with a little more detail and middle steps than outlined above? - Taxman ^Talk 16:51, September 3, 2005 (UTC)

[edit] Stub?

Is there really much more to add to this article? I'm kind of new to the whole wikipedia thing and I was looking for something I could expand in and find the FOIL article. It looks fairly complete to me, any comments? —The preceding unsigned comment was added by Mlw1235 (talk • contribs).

What about the process of "unfoiling"... —The preceding unsigned comment was added by 69.234.165.36 (talk • contribs).

I assume you mean factoring. - dcljr (talk) 17:08, 23 May 2006 (UTC)

Possibly the history of the subject? A see also section? --TeaDrinker 19:22, 23 May 2006 (UTC)