2.01   Review of Factoring

Intermediate Algebra: One Step at a TimePages 139 - 142:   #33, 37, 51, 52, 56

Dr. Robert J. Rapalje

Seminole State College of Florida

Sanford, FL  32773

 

To see Section 2.01, with explanations, examples, exercises, and answers, click here!

 

 

Guidelines to Factoring

 

  1. Common Factor
  2. Trinomials
  3. Difference of Squares; Difference and Sum of Cubes
  4. Grouping

 

 

 

p. 140.  #33.           

Next, notice that this is a SUM of two cubes!  The  FIRST is  , which is actually and the SECOND is which can be written  .  Remember  that the sum of two cubes factors into the product of a binomial times a trinomial in this form, according to the formula .  

What you have is:

                                         

                                                 

                             

                             

                             

 

p. 141.  #37.        

The first step in any factoring problem should be to take out the common factor.  In this case the common factor is

                                   

                                   

Next, notice that this is a SUM of two cubes!  The  FIRST is  , which is actually and the SECOND is which can be written  .  Remember  that the sum of two cubes factors into the product of a binomial times a trinomial in this form, according to the formula

 .  

What you have is:

                             

                                           

                         

                       

                       

p. 142.  # 51.        

Solution: 

This is a grouping problem in which it works to group the first two terms together and the second two term together.  From the first two terms you can take out a common factor of .  From the second two terms, there really isn’t a common factor to take out, so just factor out a .

                              

Now there is a common factor of , so take out the common factor:

                               

Next, factor the difference of two squares:

                             

And again, the difference of two squares:

                              

p. 142.  # 52.         

Solution: 

You may have guessed from the grouping by parentheses and by the colors used in this problem, that it is a trinomial.  Factor the first grouping as a trinomial, then factor the middle two terms by taking out a common factor of 4, and leave the last 4 alone:

                              

                               

                             

Now, the entire problem is a trinomial, which factors:

                           

It looks nicer if you clean it up:

                               

And even better, you can write it like this:

                                         

p. 142.  # 56.         

Solution: 

This is a grouping problem in which it works to group the first two terms together and the second two term together.  From the first two terms you can take out a common factor of .  From the second two terms, there really isn’t a common factor to take out, so just factor out a .

                              

Now there is a common factor of , so take out the common factor:

                               

Next, factor the difference of two squares:

                             

And again, the difference of two squares:

                              

 

Return to main page       Math in Living C O L O R !!

     Return to Basic Algebra page     Return to Intermediate Algebra page  

 Return to College Algebra page

 

 

Dr. Robert J. Rapalje Altamonte Springs Campus
Contact me at:   rapaljer@seminolestate.edu
Phone number:  NONE Retired!!
OFFICE:          NONE  
Copyright © Seminole State College of Florida, 1997