Question

(-i)^73

Answer 1

-1

Answer 2

for any multiple of 4, then \(\large i^{4k}=1 \), k is a positive integer.
since 72 is a multiple of 4 then \(\large i^{72}=1 \)
so \(\large (-i)^{73}=(-i)^{72}\cdot (-i)^1= (1)\cdot (-i)^1=-i \)