How do you factor $256a^3 + 4$ ?

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Answer 1 · 2018-03-17T01:54:30

$4(4a+1)(16a^2-4a+1)$

Given: $256a^3+4$

Factor out the greatest common factor.

$=4(64a^3+1)$

Now, we need a simple observation that $64a^3=(4a)^3$ .

$=4((4a)^3+1^3)$

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

$=4(4a+1)(16a^2-4a+1)$

How do you factor 256a^3 + 4256a^3 + 4?