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The history of Baoshan District 20 14 is the same.
Solution: Let A be the symmetry point D of OB, connect CD to OB to P, connect AP, and let D be DN⊥OA to N, then the value of PA+PC is the smallest at this time.

∫ rt △ the coordinate of OAB vertex A is (9,0),

∴OA=9,

∫tan∠BOA = 33,

∴AB=33,∠B=60,

∴∠AOB=30,

∴OB=2AB=63,

According to the triangle area formula, s △ OAB =12× OA× ab =12× ob× am, that is, 9×33=63AM.

∴AM=92,

∴AD=2×92=9,

∠∠AMB = 90,∠B=60,

∴∠BAM=30,

∫∠BAO = 90,

∴∠OAM=60,

∵DN⊥OA,

∴∠NDA=30,

∴AN= 12AD=92, which is obtained by Pythagorean theorem: DN=AD2? AN2