Answer:
10i
Step-by-step explanation:
Step 1: Expand first 2
(1 + i)(2 + i)
2 + i + 2i + i²
2 + 3i + (-1)
1 + 3i
Step 2: Expand again
(1 + 3i)(3 + i)
3 + i + 9i + 3i²
3 + 10i + 3(-1)
3 + 10i - 3