How do you factor $27+8x^3$ ?

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Answer 1 · 2016-02-05T00:23:34

$27+8x^3=(3+2x)(9-6x+4x^2)=(2x+3)(4x^2-6x+9)$

The sum of two cubes can be factored as:

$a^3+b^3=(a+b)(a^2-ab+b^2)$

For the problem at hand, $27+8x^3=3^3+(2x)^3$ so that $a=3$ and $b=2x$ . Therefore

$27+8x^3=(3+2x)(9-6x+4x^2)=(2x+3)(4x^2-6x+9)$

Answer 2 · 2016-02-05T00:24:39

It is $27+8x^3= (3+2x)*(9-6x+4x^2)$

Rewrite this as follows

$27+8x^3=(3^3)+(2x)^3=(3+2x)*(3^2-6x+4x^2)= (3+2x)*(9-6x+4x^2)$

How do you factor 27+8x^327+8x^3?