Answer:
Step-by-step explanation:
[tex]p^4-81=(p^2)^2-9^2=(p^2+9)(p^2-9)=(p^2-9(-1))(p+3)(p-3)\\=(p^2-9i^2)(p+3)(p-3)\\=(p+3i)(p-3i)(p+3)(p-3)[/tex]
