1. A3 4.1e To Factor the Sum of Two Cubes And the Difference of Two Cubes
A3 4.1e To Factor the Sum of Two Cubes
And the Difference of Two Cubes

2. Active Learning Assignment?4

3. FACTORING RULES!
Always see if you can factor out a common term. COUNT TERMS!!!
TWO TERMS: a.) Difference of Two Squares: a2 – b2 = (a + b) (a – b)
b.) Sum of Two Cubes: a3 + b3 = (a + b) (a2 – ab + b2)
c.) Difference of Two Cubes: a3 – b3 = (a – b) (a2 + ab + b2)

4. Also remember that perfect cube powers are multiples of 3.
Extra: Use your calculator to find roots:
Power
Root
(If you want the 3rd root, do this first.)
(Use parentheses!)
(Above the ^ on TI 30-X)
Also remember that perfect cube powers are multiples of 3. 10 4

5. Ex: 1. x3 + 8 Try: 2. x6 + y6 a = x & b = 2 a = x2 & b = y2
LESSON: Remember, you have a list of perfect cubes on your cube sheet.
The formulas are:
Sum of Two Cubes: a3 + b3 = (a + b) (a2 – ab + b2)
Difference of Two Cubes: a3 – b3 = (a – b) (a2 + ab + b2)
FIRST, determine what “a” and “b” are.
Ex: x3 + 8
Try: x6 + y6
a = x & b = 2
a = x2 & b = y2
(a + b) (a2 – ab + b2)
(a + b) (a2 – ab + b2)
(x + 2) (x2 – 2x + 4)
(x2 + y2) (x4 – x2 y2 + y4)

6. Ex: 3. x6 – 125 Try: 4. 8x3 – y9 a = x2 & b = 5 a = 2x & b = y3
The formulas are:
Sum of Two Cubes: a3 + b3 = (a + b) (a2 – ab + b2)
Difference of Two Cubes: a3 – b3 = (a – b) (a2 + ab + b2)
FIRST, determine what “a” and “b” are.
Ex: x6 – 125
Try: x3 – y9
a = x2 & b = 5
a = 2x & b = y3
(a – b) (a2 + ab + b2)
(a – b) (a2 + ab + b2)
(x2 – 5) (x4 + 5x2 + 25)
(2x – y3) (4x2 + 2xy3 + y6)

7. Factor Sum or Difference of 2 Cube worksheet Odds.
Remember, the formulas are:
Sum of Two Cubes: a3 + b3 = (a + b) (a2 – ab + b2)
Difference of Two Cubes: a3 – b3 = (a – b) (a2 + ab + b2)
Determine what “a” & “b” are.
x9 – y15
a = 5x3 & b = y5
(5x3 – y5) (25x6 + 5x3y5 + y10)
x y18
2(8x y18)
a = 2x4 & b = 3y6
2 (2x4 + 3y6) (4x8 – 6x4y3 + 9y12)
Factor Sum or Difference of 2 Cube worksheet Odds.