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Problem 8 (2022 AIME I)

AIME 2022
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Understand the scale
Scale 0.5: Easiest math competition problems, often solvable even for early middle school students without experience. 1: Problems strictly for beginners, often at a moderate middle school level. 1.5: Problems for stronger beginner students, on the level of the middling problems in most middle school contests. 2: For motivated beginners, harder questions from the previous categories. 2.5: More advanced beginner problems, hardest questions from previous categories. 3: Early intermediate problems that require more creative thinking. 3.5: Tougher early intermediate problems that consistently stretch into higher-level creative thinking or conceptual knowledge. 4: Intermediate-level problems. 4.5: Upper intermediate problems approaching the upper bound for non-invitational sprint math competitions. 5: More difficult AIME problems or simple proof-based Olympiad-style problems. 6: High-level AIME-styled questions or introductory Olympiad-level questions. 7: Tougher Olympiad-level questions, may require more technical knowledge. 8: High-level Olympiad-level questions. 9: Expert Olympiad-level questions. 9.5: The hardest problems appearing on Olympiads which the strongest students could reasonably solve. 10: Historically notorious problems, generally unsuitable for even very hard competitions because they are exceedingly tedious, long, and difficult.

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Problem

Equilateral triangle △ABC\triangle ABC is inscribed in circle ω\omega with radius 18.18. Circle ωA\omega_A is tangent to sides AB‾\overline{AB} and AC‾\overline{AC} and is internally tangent to ω.\omega. Circles ωB\omega_B and ωC\omega_C are defined analogously. Circles ωA,\omega_A, ωB,\omega_B, and ωC\omega_C meet in six points---two points for each pair of circles. The three intersection points closest to the vertices of △ABC\triangle ABC are the vertices of a large equilateral triangle in the interior of △ABC,\triangle ABC, and the other three intersection points are the vertices of a smaller equilateral triangle in the interior of △ABC.\triangle ABC. The side length of the smaller equilateral triangle can be written as a−b,\sqrt{a} - \sqrt{b}, where aa and bb are positive integers. Find a+b.a+b. Diagram $

figure

$ ~MR ENTHUSIASM ~i hate math123

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