Answer:
-i
Step-by-step explanation:
i = [tex]\sqrt{-1}[/tex]
[tex]i^{2}[/tex] = - 1
Every [tex]i^{x}[/tex] will be equal to -1, when n is even.
Break apart [tex]i^{39}[/tex] into ([tex]i^{38}[/tex])([tex]i^{1}[/tex])
Since 38 is even, [tex]i^{38}[/tex] will be equal to -1
-1*([tex]i^{1}[/tex]) = -i
