Question

(a+i)^4 me ajudem a responder, por gentileza.

Answer 1

[a + i]^4 =
( [a + i]^2 )^2 =
[a^2 + 2ai + i^2]^2 =
[a^2 + 2ai - 1]^2 =
a^4 + 2a^3i - 2a^2 + 4a^2i^2 - 2ai + 1 =
a^4 + 2a^3i - 2a^2 - 4a^2 - 2ai + 1 =
a^4 + 2a^3i - 6a^2 - 2ai + 1