SOLUTION: I need help factoring the difference of these cubes. 54x^3-16y^3

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Question 182225: I need help factoring the difference of these cubes.
54x^3-16y^3
Found 2 solutions by Alan3354, stanbon:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
I need help factoring the difference of these cubes.
54x^3-16y^3
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If you divide it by 2, you get
2*(27x^3 - 8y^3) which is
2%2A%28%283x%29%5E3+-+%282y%29%5E3%29
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Can you take it from there? A difference of 2 cubes?
I'll add a hint.
a%5E3+-+b%5E3+=+%28a-b%29%2A%28a%5E2+%2B+ab+%2B+b%5E2%29

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
I need help factoring the difference of these cubes.
54x^3-16y^3
= 2((3x)^3 - (2y)^3)
= 2(3x - 2y)((3x)^2 + (3x)(2y) + (2y)^2)
= 2(3x-2y)(9x^2 + 6xy + 4y^2)
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Cheers,
Stan H.