Question

give the derivation of identityused for

$(x + y + z) {}^{2}$
​

Answer 1

HEY DEAR_______❤❤❤❤❤

HERE IS YOUR ANSWER:-)

⬇⬇⬇⬇⬇⬇⬇⬇

=>IDENTITY....

=>> ( x + y + z )^2

=>(x + y + z)^2 = x^2 + y^2 + z^2 + 2xy + 2yz + 2zx

Proof:

Let x + y = k then,

(x + y + z)^2 = (k + z)^2

= k^2 + 2kz + z^2 (Using identity I)

= (x + y)^2 + 2(x + y)z + z^2

= x^2 + 2xy + y^2 + 2xz + 2yz + z^2

= x^2 + y^2 + z^2 + 2xy + 2yz + 2zx (proved)

HOPE IT HELPS YOU...

^_^

Answer 2

Holaaa Mate

Answer:

✔️(x + y + z)^2 = x^2 + y^2 + z^2 + 2xy + 2yz + 2zx

✔️Proof:

Let x + y = a then,

(x + y + z)^2 = (a + z)^2

= a^2 + 2az + z^2 (Using identity 1)

= (x + y)^2 + 2(x + y)z + z^2

= x^2 + 2xy + y^2 + 2xz + 2yz + z^2

= x^2 + y^2 + z^2 + 2xy + 2yz + 2zx

HENCE PROVED..