Răspunsuri

2014-01-22T14:28:33+02:00
(a^3-c^3)/(a-c)=(a-c)(a^2+ac+c^2)/(a-c)=a^2+ac+c^2
(a^3-b^3)/(a-b)=(a-b)(a^2+ab+b^2)/(a-b)=a^2+ab+b^2
(b^3-c^3)/(b-c)=(b-c)(b^2+bc+c^2)/(b-c)=a^2+ac+c^2

(a^3-c^3)/(a-c)=(a^2+ab+b^2+a^2+ac+c^2)/2