Question

Calcule:
a) (5 + 8i) + (0 - i)
b) (-4 + 2i) + (5 - 3i)
c) (-1 + 9i) - (2 - 8i)
d) (7 + 6i) * (7 - 3i)
e) (5 + 6i) * (4 +8i)

Answer 1

a) (5+8i) + (0-i)
5+8i +(-i )
5+8i-i
5+7i

Answer 2

a) 5 + 7i
b) 1 - i
c) -3 + 17i
d) 49 - 21i + 42i - 18i = 49 + 3i
e) 20 + 40i + 24i + 48i = 20 + 112i