The Total solution for NCERT class 6-12
(a + b + c)2 =a2 + b2 + c2 + 2(ab + bc + ca)⇒ (9)2 = a2 + b2 +c2 + 2 x23⇒ 81= a2 +b2 + c2 + 46⇒ a2 + b2 +c2 = 81 – 46 = 35∴ a2 + b2 + c2 =35