Question

A2 _ab,b2 bc and c2 +ca ka ans

Answer 1

Step-by-step explanation:

Here we will express a2 + b2 + c2 – ab – bc – ca as sum of squares.

a2 + b2 + c2 – ab – bc – ca =

1

2

{2a2 + 2b2 + 2c2 – 2ab – 2bc – 2ca}

=

1

2

{(a2 + b2 – 2ab) + (b2 + c2 – 2bc) + (c2 + a2 – 2ca)}

=

1

2

{(a - b)2 + (b - c)2 + (c – a)2}