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• 1995 IMO Problems/Problem 1
  ''Lemma:'' The radical axis of two pairs of circles <math>O_1</math>, <math>O_2</ma The proof of this lemma is trivial using the argument in Solution 3 and applying the converse of Po
  5 KB (847 words) - 19:03, 12 October 2021
• 2024 USAJMO Problems/Problem 3
  Lemma <math>1</math>: Proof of Lemma <math>1</math>:
  2 KB (469 words) - 11:39, 28 March 2024