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Mock USAMO by probability1.01 dropped problems

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Contents

Problem 1

Solution

Problem 2

In triangle , , let the incircle touch , , and at , , and respectively. Let be a point on on the opposite side of from . If and meet at , and and meet at , prove that , , and concur. Reason: The whole incircle business seemed rather artificial. Besides, it wasn’t that difficult.

Image:Mock_usamo.png

Solution

Problem 3

Solution

Problem 4

Solution

Problem 5

Solution

Problem 6

Solution

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