For acute triangle ABC, the first call is the midpoint of side AB. Circle (T) of a triangle AIC cut BC at D. Circle (S) J Center inscribed triangle ADC. Central line of the circle cut piece CJ (T) at two points E, F (E located on the same side with A through BC). IE cut AC at P, IF cut BC in H.
a) Prove that the straight lines AF, DE, PH and go through a point.
b) The circle (S) in contact with the sides AD, AC triangle ADC in the order in M, N. Call Q is the intersection of IE with AD. Prove that the four points M, N, P, Q and located on a circle
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