SOLUTION: Factor: 8x^6 +27

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Question 463378: Factor: 8x^6 +27
Answer by algebrahouse.com(1659) About Me  (Show Source):
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8x^6 + 27

It is a "sum of two cubes", in the form a³ + b³.
It factors into the form (a + b)(a² - ab + b²)

If a³ is 8x^6, then a is 2x² {the cube root of 8x^6}
If b³ is 27, then b is 3 {the cube root of 27}

So, substitute 2x² in for a, and 3 in for b, into:
(a + b)(a² - ab + b²)

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

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