Răspunsuri

2014-03-14T11:33:19+02:00
(a-b)^2=a^2-2ab+b^2 - asta e formula

a^2+b^2=13 
si 
ab=6

inlocuim
a^2-2ab+b^2=

13-2*6=
13-12=
1

* e inmultire
^ la a doua