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Sum it up!

Algebra Level 2

\( \sum_{k=1}^5 (k^2 + 2) \).

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Excel in math and science

Master concepts by solving fun, challenging problems.

It's hard to learn from lectures and videos

Learn more effectively through short, interactive explorations.

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including olympiad champions, researchers, and professionals.

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by Mardokay Mosazghi

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