Question 984109
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You have three factors, so you have to multiply one pair and then take that product times the third factor.  Multiplication, like addition, is a binary operation -- only two operands allowed at a time.


FOIL is a process that only works with binomials, because if you have a trinomial (or greater degree) factor, First, Outside, Inside, Last doesn't include all of the multiplications you have to do.


The process I use when multiplying polynomials with more than two terms is to take the first term of the first polynomial times each of the terms of the second polynomial, and I write them in a line making sure my signs are correct.  Then I take the second term of the first polynomial and multiply it by each of the terms in the second polynomial, writing these terms in a line UNDER the first line of terms, making sure to line up the terms by degree (the cubed terms in one column, the squared terms in another column, etc.).  Once I have multiplied each of the first polynomial's terms by each of the second polynomial's terms, I add up the columns to collect like terms.


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ (x\ +\ 2y\ -\ 3)(2x\ -\ y\ +\ 1)]


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ 2x^2\ -\ \ \,xy\ +\ \ x]
*[tex \LARGE \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ 4xy\ \ \ \ \ \ \ \ -\ 2y^2\ \,+\ 2y]
*[tex \LARGE \ \ \ \ \ \ \ \ \ \ \underline{\ \ \ \ \ \ \ \ \ \ \ \ \ \ \,-\ 6x\ \ \ \,\ \ \ \ \ \ +\ 3y\ -\ 3}]
*[tex \LARGE \ \ \ \ \ \ \ \ \ \ 2x^2\ +\ 3xy\ -\ 5x\ -\ 2y^2\ +\ 5y\ -\ 3]


John
*[tex \LARGE e^{i\pi}\ +\ 1\ =\ 0]
My calculator said it, I believe it, that settles it