Let z = (1 + i)(1 + 2i)(1 + 3i) (1 + ni), where i = -1. If |z|2 = 44200, then n is equal to .
Answer
5
Solution
|z|2 = |1 + i|2 |1 + 2i|2 |1 + ni|2
= (1 + 12)(1 + 22)(1 + 32) (1 + n2)
= 2 5 10 17 26
Products: 2, 10, 100, 1700, 44200
|z|2 = 44200 for n = 5
Answer: 5