How do you factor $3x^9-9x^7$ ?

Question

1500 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2015-05-27T00:40:12

Given $3x^9-9x^7$

Extract the common factor $3x^7$

$= (3x^7)(x^2-3)$

Treat $3$ as $(sqrt(3))^2$ for the difference of squares

$= (3x^7)(x+sqrt(3))(x+sqrt(3))$

How do you factor 3x^9-9x^73x^9-9x^7?