can you please help me understand this kind of problem? factor sum of two cube: 27x+3x^3 can you explain me by steps? thank you!
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Originally Posted by Anemori can you please help me understand this kind of problem? factor sum of two cube: 27x+3x^3 can you explain me by steps? thank you! $\displaystyle 27x+3x^3$ This isn't the sum of two cubes. Although 27 is a cube, $\displaystyle 27x$ is not a cube. Also, $\displaystyle 3x^3$ isn't a cube either. You can factor out $\displaystyle 3x$ to obtain: $\displaystyle x(27+3x^2)=3x(9+x^2)$
$\displaystyle (a^3+b^3)=(a+b)(a^2-ab+b^2)$ But this will not work for your expression as said above.
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