Răspunsuri

Cel mai inteligent răspuns!
2014-08-29T20:48:41+03:00
MN+PQ=MQ+PN  

=>MN-MQ=PN-PQ (1)

MN-MQ=QN (2)
PN-PQ=QN (3)

(2)=(3)=QN
(1)=QN
MN-MQ=PN-PQ =QN   =>MN+PQ=MQ+PN   (c.t.t.d.)

OBS: 'XY' = vector
Ce inseamna c.t.t.d. ?
ceea ce trebuia demonstrat
Multumesc!
;)