# A beautiful problem

Let $P$ be point lie on circumcircle of an equilateral triangle $\Delta ABC$. Let $(D_1D_2)//(BC) ;(E_1E_2)//(CA); (F_1F_2)// (AB)$

Prove that $D_1D_2+E_1E_2+F_1F_2=2.AB$

Author: Van Khea, Cambodia