Vermenigvuldigen en delen (a+bi)

Bereken

\(\frac{3-i}{-9-3i}\)

\(\frac{3-i}{-9-3i}= \frac{3-i}{-9-3i} \cdot \frac{-9+3i}{-9+3i} = \frac{-27+9i +9 i-3i^2 }{(-9)^2-(-3i)^2} = \frac{-27+9i +9 i+3}{81 + 9} = \frac{-24+18i }{90} = \frac{-4}{15} - \frac{-1}{5}i \)