Question

(a+b+c)^=a^+b^+c^+2ab+2bc+2ca prove that

Answer 1

I think question is,

(a+b+c)^2 =a^2 +b^2 +c^2 +2ab+2bc+2ca

Solve by LHS,

Let (b+c) = x

= (a+x) ^2 = a^2 + 2ax + x^2

Put value of x = (b+c)

= a^2 + 2a(b+c) + (b+c) ^2

= a^2 + 2ab + 2ac + b^2 + c^2 + 2bc

= a^2 +b^2 +c^2 +2ab+2bc+2ca

Hence (a+b+c)^2 =a^2 +b^2 +c^2 +2ab+2bc+2ca.. Proved.

Hope it's helpful to u.