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Algebra Level 2

Let \(i = \sqrt{-1}\). Evaluate

\[\huge i.i.\sum_{t=1}^7 t\]

Excel in math and science

Master concepts by solving fun, challenging problems.

It's hard to learn from lectures and videos

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Our wiki is made for math and science

Master advanced concepts through explanations,
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including olympiad champions, researchers, and professionals.

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by Nihar Mahajan

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