Answer:
= - 12 + 316 i
Explanation:
Given that -
z = 3 + i
=

= 9 +
+ 6 i
= 9 - 1 + 6 i
= 8 + 6 i
=
× z
= ( 8 + 6 i ) × ( 3 + i )
= 24 + 8 i + 18 i + 6 i²
= 24 + 26 i - 6
= 18 + 26 i
=
×

= ( 8 + 6 i ) × ( 18 + 26 i )
= 144 + 208 i + 108 i + 156 i²
= 144 + 316 i -156
= - 12 + 316 i