# How do you factor  243-3t^4?

Jun 29, 2016

$3 \left(9 + {t}^{2}\right) \left(3 + t\right) \left(3 - t\right)$

#### Explanation:

To factor $243 - 3 {t}^{4}$

Begin by factoring out the common factor 3

$3 \left(81 - {t}^{4}\right)$

Now recognizing $81 - {t}^{4}$ as the difference of two squares we can factor the binomial.

$3 \left(9 + {t}^{2}\right) \left(9 - {t}^{2}\right)$

Now recognizing $9 - {t}^{2}$ as the difference of two squares we can factor the binomial.

$3 \left(9 + {t}^{2}\right) \left(3 + t\right) \left(3 - t\right)$