# How do you factor -3xy^6 + 3xy^2?

It is $3 x {y}^{2} \left(1 - y\right) \left(1 + y\right) \left(1 + {y}^{2}\right)$
$- 3 x {y}^{6} + 3 x {y}^{2} \implies 3 x {y}^{2} \left(- {y}^{4} + 1\right) \implies 3 x {y}^{2} \left(1 - {y}^{2}\right) \left(1 + {y}^{2}\right) \implies 3 x {y}^{2} \left(1 - y\right) \left(1 + y\right) \left(1 + {y}^{2}\right)$