Question

(a+b+c)(a-bc)(a2+b2+c2)​

Answer 1

Answer:

Here we will express a2 + b2 + c2 – ab – bc – ca as sum of squares. a2 + b2 + c2 – ab – bc – ca = 12{2a2 + 2b2 + 2c2 – 2ab – 2bc – 2ca}