Question 375288
i^4 = 1
i^199 = i^3 * i^196 = i^3 * (i^4)^49 = i^3 * 1^49
i^199 = i^3 = i * i^2 = -i
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To sum it up:
Divide the exponent by 4 and keep the remainder
199/4 = 49 + remainder 3
= i^3