Question

When factored completely, the expression p^4-81 is equivalent to what?

Answer 1

Hello,

p^4-3^4=(p²+9)(p²-9)=(p-3)(p+3)(p²+9) [in R]
[(maybe (p-3)(p+3)(p-3i)(p+3i) in C]

Answer 2

Differnce of 2 pefect squares
a^2-b^2=(a-b)(a+b)
(p^2)^2-9^2=(p^2-9)(p^2+9)

p^2-9=(p-3)(p+3)

factored is
(p-3)(p+3)(p^2+9)