Answer: 15 = -i & 12=1
use the pattern : i, -1, -i, 1
Step-by-step explanation:
i = [tex]\sqrt{-1}[/tex]
[tex]i^{2}[/tex] = [tex]\sqrt{-1}[/tex]
[tex]i^{3}[/tex] = [tex]\sqrt{-1}[/tex]
[tex]i^{4}[/tex] = [tex]\sqrt{-1}[/tex]
the pattern just repeats from here
5 = i
6 = -1
7 = -i
8 = 1
9 = i
10 = -1
11 = -i
12 = 1
13 = i
14 = -1
15 = -i
16 = 1
