SOLUTION: Factor completely. 8x^3 - 27

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Question 384876: Factor completely.
8x^3 - 27
Found 2 solutions by ewatrrr, fcabanski:
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi,         

Factoring completely

 8x^3 - 27 = (2x)^3 - 3^2 

In general: x^3 - a^3 = (x-a)(x^2 -ax + a^2)

In this example:  x is '2x'

(2x + 3)((2x)^2 - (2x)(3) + 3^2) 

(2x + 3)(4x^2 - 6x + 9 )

Answer by fcabanski(1391) About Me  (Show Source):
You can put this solution on YOUR website!
The given solution is not correct.


The following is the correct answer.


x%5E3+-+a%5E3+=+%28x-a%29%28x%5E2+%2Bax+%2B+a%5E2%29


In this example: x is '2x'


%282x%29%5E3+-+3%5E3


%282x+-+3%29%28%282x%29%5E2+%2B+%282x%29%283%29+%2B+3%5E2%29+


%282x+-+3%29%284x%5E2+%2B+6x+%2B+9+%29

Hope the solution helped. Sometimes you need more than a solution. Contact fcabanski@hotmail.com for online, private tutoring, or personalized problem solving (quick for groups of problems.)