Answer:
Step-by-step explanation:
d^4-81
(d^2)^2-(9)^2
Using formula
(d^2+9)(d^2-9)
Answer:
(d - 3)(d + 3)(d² + 9)
Step-by-step explanation:
[tex]d^{4}[/tex] - 81 ← can be factored as a difference of squares
a² - b² = (a - b)(a + b), thus
[tex]d^{4}[/tex] - 81
= (d²)² - 9²
= (d² - 9)(d² + 9)
Note that d² - 9 is also a difference of square, so
= (d - 3)(d + 3)(d² + 9) ← in factored form
