Вычислите : ( 5+4i) (-2+3i)

Question

Вычислите : ( 5+4i) (-2+3i)

Answer 1

(5 + 4i)(- 2 + 3i) = 5 * (- 2) + 5 * 3i + 4i * (- 2) + 4i * 3i = - 10 + 15i - 8i + 12i² =

= - 10 + 7i + 12 * (- 1) = - 10 + 7i - 12 = 7i - 22