How do you factor $2x^3-18x$ ?

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Answer 1 · 2016-12-04T00:07:29

$2x^3-18x = 2x(x-3)(x+3)$

Separate out the common factor $2x$ , then use the difference of squares identity:

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

with $a=x$ and $b=3$ as follows:

$2x^3-18x = 2x(x^2-9)$

$color(white)(2x^3-18x) = 2x(x^2-3^2)$

$color(white)(2x^3-18x) = 2x(x-3)(x+3)$

How do you factor 2x^3-18x2x^3-18x?