Question

Efetue as operações:

A) (-3 + 1) + (-2 - 5i)
B) (-2 + 3i) + (1 - 2i) + (3 - 5i)
C) 3. (7 + 2i) - [(5 + 4i) + 1] . i

Answer 1

a) (2 + 5i) * (1 – 2i)

2 – 4i + 5i – 10i² (lembrando que i² = – 1)

2 – 4i + 5i – 10 * (–1)

2 – 4i + 5i + 10

12 + i

b) (4 + 3i) * (2 + 6i)

8 + 24i + 6i + 18i² (lembrando que i² = – 1)

8 + 24i + 6i + 18 * (–1)

8 + 24i + 6i – 18

–10 + 30i

c) (6 – 3i) * (–3 + 7i)

–18 + 42i + 9i – 21i² (lembrando que i² = – 1)

–18 + 42i + 9i – 21 * (–1)

–18 + 42i + 9i + 21

3 + 51i