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Question
Find the value of the following expression:
i + i2 + i3 + i4
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Solution
\[ i + i^2 + i^3 + i^4 \]
\[ = i - 1 - i + 1 \left[ \because i^2 = - 1, i^3 = - i \text { and } i^4 = 1 \right]\]
\[ = 0 \]
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