Answers:

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Step-by-step explanation:
By definition,

Squaring both sides gets us

Then multiply both sides by i to get

Repeat the last step and you should get

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Notice we have this pattern going on:

Once we reach i^4, we start the process over again.
It repeats every 4 terms.
This means we'll divide the exponent over 4 and look at the remainder. We ignore the quotient completely.
157/4 = 39 remainder 1
That remainder 1 is the exponent of the simplified term

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Similarly,
315/4 = 78 remainder 3
So

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102/4 = 25 remainder 2

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76/4 = 19 remainder 0
