The Best Way to Factor Trinomials – A Practice CDF Program

I have created a Mathematica object that people can use to practice factoring trinomials the “best” way.  It is a CDF file (computable document file) and requires a CDF plug-in which can be found here.  Once you have the plug-in you can go to Mathematics‘  demonstration site here and browse through wondrous mathematical demos.

The trinomial practice object is located here.   Sometimes it stops working for unknown reasons.  All I can say is reload and start again.

As you work through the problems, you will see that the method generalizes beautifully.  For instance, if you are factoring 15x^2+51x+18, you might not notice the greatest common factor of 3.  If this 3 was factored out, the trinomial would be easier to factor, but the method doesn’t care.  Here is the example worked out.

Factoring Example - Greatest Common Factor

A factoring problem that gives students trouble is something like this 3x^2+5x.  Append a zero and using the “best” factoring method as done in the example.

Factoring Example - Append a Zero

And finally what if we had to factor 3x^2.  It is already factored and the “best” factoring knows it as in this example.

Factoring Example - Append Two Zeros

The “best” way to factor trinomials is fun to learn and very useful.  Give it a try.


About jrh794

I am a sixty-five year old math instructor at Southern Oregon University. I taught at the College of the Siskiyous in Weed California for twenty-six years. Prior to that I worked as a computer programmer, carpenter and in various other jobs. I graduated from Rice University in 1967 and have a MS in Operations Research from Stanford. In the past I have hand-built a stone house and taken long solo bicycle tours. Now I ride my mountain bike and play golf for recreation.
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