<s>[INST] Multiplying binomials to come up with $ y^8 - 256 $ $$\ { (y^4 + 16) }{ (y^2 + 4) }{ (y + 2) }{ (y - 2) }$$
How do I multiply these to come up with $\ {y^8 - 256}$
 [/INST] $$(a+b)(a-b)=a^2-b^2$$
$$\ { (y^4 + 16) }{ (y^2 + 4) }\color{red}{{ (y + 2) }{ (y - 2)} }=(y^4+16)(y^2+4)\color{red}{(y^2-4)}$$
$$(y^4+16)\color{red}{(y^2+4){(y^2-4)}}=(y^4+16)\color{red}{(y^4-16)}$$
$$\color{red}{(y^4+16)(y^4-16)}={(y^8-256)}$$
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