Algebra I dealt with some factoring--we leaned how to factor equations
of the form a2 + bx + c, as well as perfect square
trinomials and the difference of
squares. This chapter explains
how to factor other polynomials.
Section one explains how to factor trinomials of degree 2 with a
leading coefficient--that is,
trinomials of the form ax2 + bx + c, where a, b, and c are
integers. This section outlines the steps for factoring these
trinomials. The process for factoring ax2 + bx + c is a
generalization of the process for factoring x2 + bx + c, which we
learned in Algebra I.
The second section explains how to factor some polynomials of degree 3.
First, it deals with polynomials which are the difference of cubes,
then with polynomials which are the sum of cubes. Finally, the
second section explains how to factor equations of the form ax3 + bx2 + cx + d where
=
.
The next section focuses on fourth degree polynomials. It
explains how to factor a difference of fourth powers, as well as some
fourth-degree trinomials.
Finally, in the fourth section, we learn one of the most important uses
of factoring--finding roots. The roots of a function are the
solutions to f (x) = 0; i.e. the points at which y = f (x) crosses
the x-axis. Learning how to find roots will help when graphing
polynomial equations. Learning how to find the number of roots
will also allow us to approximate the shape of a graph without plugging
in points.
Finding the roots of an equation becomes especially important in the
study of polynomials in Algebra II and higher mathematics.
Thus, it is
crucial to understand how to factor an equation. Factoring takes
practice; it is more useful to try several problems and get a feel for
factoring than it is to memorize a set of steps for factoring. This
chapter does provide a set of steps--they are meant to be used as a
framework or skeleton until the reader becomes more familiar with
factoring. The reader is encouraged to practice factoring, as it will
come up a lot in Algebra II.