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How do you factor 2x^3+5y^3

1 Answer

5 votes
All you do is...

\mathrm{Apply\:sum\:of\:cubes\:rule:\:}x^3+y^3=\left(x+y\right)\left(x^2-xy+y^2\right)


2x^3+5y^3=\left(\sqrt[3]{2}x+\sqrt[3]{5}y\right)\left(\left(\sqrt[3]{2}\right)^2x^2-\sqrt[3]{2}\sqrt[3]{5}xy+\left(\sqrt[3]{5}\right)^2y^2\right)

\left(\sqrt[3]{2}x+\sqrt[3]{5}y\right)\left(\left(\sqrt[3]{2}\right)^2x^2-\sqrt[3]{2}\sqrt[3]{5}xy+\left(\sqrt[3]{5}\right)^2y^2\right) \ \textgreater \ Refine


\left(\sqrt[3]{2}x+\sqrt[3]{5}y\right)\left(2^{(2)/(3)}x^2-\sqrt[3]{10}xy+5^{(2)/(3)}y^2\right)

Hope this helps!
User HassenPy
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