Sum or Difference of Cubes
A polynomial in the form a 3 + b 3 is called a sum of cubes. A polynomial in the form a 3 – b 3 is called a difference of cubes.
Both of these polynomials have similar factored patterns:
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A sum of cubes: 
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A difference of cubes: 
Example 1
Factor x 3 + 125.
Example 2
Factor 8 x 3 – 27.
Example 3
Factor 2 x 3 + 128 y 3.
First find the GCF. GCF = 2 
Example 4
Factor x 6 – y 6.
First, notice that x 6 – y 6 is both a difference of squares and a difference of cubes.
In general, factor a difference of squares before factoring a difference of cubes.
