Unformatted text preview: (b) Determine the value oF the digit a such that the number 2-17-8a2250-3 is a valid ISBN. (c) When an ISBN was copied, two adjacent digits were interchanged resulting in the number 1-18-397604-5. Determine the original ISBN. Problem 2 . A positive integer is divisible by 8 iF and only iF the three-digit integer Formed by its fnal three digits is divisible by 8. (You do not need to prove this.) Determine all pairs oF digits ( a, b ) such that 72 b 9 a 2 is divisible by 88. Problem 3 . Use mathematical induction to show that 3 n ≡ 1+2 n 2 (mod 8) For all integers n ≥ 0. Problem 4 . Suppose that a, b ∈ Z and m, n ∈ P . Prove that an ≡ bn (mod mn ) iF and only iF a ≡ b (mod m ). 1...
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- Spring '10
- ISBN, Natural number, Prime number, International Standard Book Number, check digit