Question

Números Complexos
Efetue:
a) (2+i)$^{2}$ - i.(2+i) - (2-i) =
b) (1+i)2 -ao quadrado- =
c) (1+i)$^{2}$ - (1-i)

Answer 1

a) (2+i) - i.(2+i) - (2-i) =
4 + 4i + i^2 -2i - i^2 - 2 + i =>
4 - 2 +4I -2I - i ==> 2 + i

b) (1+i)2 =1 +  2i +i^2 ==> 1 + 2i - 1 ==> 2i
c) (1+i) - (1-i) = 1 +  2i +i^2 - 1 + i ==> 1 -1-1 +2i +i ==> 1 + 3i