Given : a2+b2+c2−ab−bc−ca Where a,b and c are distinct real numbers (a≠b≠c) Formula used: a2+b2+c2−ab−bc−ca=
1
2
[(a−b)2+(b−c)2+(c−a)2] Calculations : It is given a,b and c are distinct real numbers Let us take the value of a=1,b=2 and c=3(a<b<c) We know that, a2+b2+c2−ab−bc−ca=
1
2
[(a−b)2+(b−c)2+(c−a)2] ⇒
1
2
(1−2)2+(2−3)2+(3−1)2] ⇒(1∕2)(1+1+4) ⇒(6∕2)=3 ⇒
1
2
[(a−b)2+(b−c)2+(c−a)2] is always positive Therefore, (a2+b2+c2−ab−bc−ca) not depend on the statement - I and statement - II ∴ Neither Statement - I nor Statement - II is required to answer the question