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Algebra Revisited
Reference: Computations and Algebraic Manipulations
Common Identities/Formulas and Algebraic Maneuvers
Common Polynomial Identities, Expansions, and Factorizations
Working with Integers and Arithmetic
Divisibility Rules
Divisibility by 3, 9, 11, 10^k ± 1
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To check whether a number is divisible by 10k^kk - 1 we take k digits from the end of the number and keep adding to this number the next k digits until we exhaust the original n…
By Dimitri Boscainos
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