Answer: D) 0
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Explanation:
Take note of this pattern
- i^0 = 1
- i^1 = i
- i^2 = -1
- i^3 = -i
- i^4 = 1
After this point, we repeat the cycle. The cycle is 4 units long. This means we can divide the exponent over 4 and look at the remainder
99/4 = 24 remainder 3
So i^99 = i^3
which means i^99 - i^3 = i^3 - i^3 = 0
