fz=3i 2 + 3i ⇒fz=3i 2 + 3i × 2 - 3i 2 - 3i ⇒fz=6i - 9i2 22 - 32i2 ⇒fz=6i + 9 4+9 ⇒fz= 9 + 6i 13 ⇒fz=9 13 +6i 13 ⇒Re(f(z))=9 13 & Im(f(z))=6 13