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Combinatorics - Please show me how to solve step by stepso I understand. Thank you.
2. Suppose that you are given n + 1 different positive integers less than or equal to 2n. Show that 48 Chapter 4 [H] (i) there exists a pair of them which adds up to 2n + 1, (ii) there must exist two which are relatively prime (i.e. that have no factors larger than 1 in common), [H] (iii) there exists one which is a multiple of another. [H]