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Yangpu Sanmao Mathematics 20 15
Solution: connect AO and extend the intersection BC to point h, connect OC,

AB = AC,

∴AB=AC,

O is the center of the circle,

∴AH⊥BC,BH=HC,

∴HC=3,

Radius OC=5,

∴OH=4,AH=9,

∴, tan∠HAC=HCAH=39= 13 in Rt△AHC, that is, tan∠OAE= 13.

D and e are the midpoint of AB side and AC side, respectively.

∴DE∥BC,

∴AH⊥DE,

∴∠OAE+∠AED=90,

∫E is the midpoint of the side AC, and o is the center of the circle.

∴OE⊥AC,

∴∠AED+∠OED=90,

∴∠OAE=∠OED,

∴tan∠OED=tan∠OAE= 13.

The tangent of ∴∠OED is: 13.