Log in to add a comment

## Answers

⇒a^2+ab+ac+ab+b^2+bc+ac+bc+c^2

⇒a^2+b^2+c^2+2ab+2bc+2ca

Hence proved

(x + y + z) = (t +z) ²

= ( t² + 2tz + t²)------------------ ( using identity I)

= (x +y )² + 2(x+y)z + z²----------( sub the value t )

= x² + 2xy + y² = 2xz +2yz + z²----------(identity I)

x²+y²+z²+2xy+2xy+ 2yz+2 zx