AM=AB+BM
AM=AC+CM
=========2AM=AB+AC+BM+CM=AB+AC/2
AM=1/2(AB+AC),SUNT VECTORI ,am aplicat regula triunghiu;ui in ABM siAMC
b)BN=BA+AN
BN=BC+CN
=========2BN=BA+BC+(AN+CN)=1/2 (BA+BC)=1/2 ORI(2BC+2BM)=BP+BM
AN+CN=0
c)CP=CB+BP
CP=CA+AP
==========
2ACP=CB+CA+BP+AP
CP=1/2(CB+CA)+0
CB=CA+AB,CA=-AC,DECI CP=-ac=1/2ab