It is known that on the BC side of the triangle ABC, be = CF is cut to connect AE AF, which means that ab + AC is greater than AE + AF

It is known that on the BC side of the triangle ABC, be = CF is cut to connect AE AF, which means that ab + AC is greater than AE + AF

Take the midpoint o of BC, connect and extend Ao to D, so that OD = OA, connect BD, ED, FD, CD, and then extend AE to intersect BD to g, then the quadrilateral abdc is a parallelogram.. BD = AC, | AB + AC = AB + BD. ∵ ob = OC, be = CF, | OE = of, and the | quadrilateral AEDF is also a parallelogram.. de = AF, AE + AF = AE + De