MathDB

Let a triangle

ABC

inscribed in circle

c(O,R)

and

D

an arbitrary point on

BC

(different from the midpoint).The circumscribed circle of

BOD

,which is

(c_1)

, meets

c(O,R)

K

and

AB

Z

.The circumscribed circle of

COD

(c_2)

,meets

c(O,R)

M

and

AC

E

.Finally, the circumscribed circle of

AEZ

(c_3)

,meets

c(O,R)

N

.Prove that

\triangle{ABC}=\triangle{KMN}.

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