Odpowiedzi

2009-09-12T13:48:21+02:00
(a-b)²≥0
a²-2ab+b²≥0
a²+b²≥2ab /:ab
a²/ab+b²/ab≥2
a/b+b/a≥2

(a-b)²≥0
a²-2ab+b²≥0 /2
2a²-4ab+2b²≥0
3a²-a² -3ab-ab +3b²-b²≥0
3a²-3ab+3b²≥a²+ab+b² /:(a²+ab+b²)
3(a²-ab+b²)/(a²+ab+b²) ≥ 1 /:3
(a²-ab+b²)/(a²+ab+b²) ≥ 1 /3