Solution. Let f be a polynomial that has roots a 2 ,b2 ,c 2 , then f(t)=(t−a2 )(t−b2 )(t−c2 ) = t3 − (a 2 + b 2 + c2 )t2 +(a2 b 2 + b2 c 2 + c2 a 2 )t− (abc)2 . If a 2 + b2 + c2 = 2 then we have f(t)=(t−a2 )(t−b2 )(t−c2 ) = t3 − 4t2 +(a2 b 2 + b2 c 2 + c2 a 2 )t− (abc)2