Question

What is the proof for (a+b)²=a²+b²+2ab

Answer 1

take some numbers like..
let a =1 and b = 2 and now substitute the values which you have taken in the identity.
(1+2)²=1²+2²+2×1×2
and now solve the L.H.S and the R.H.S. and see that L.H.S is equal to R.H.S.
1+4=1+4+4
5=9
therefore the L.H.S is not equal to R.H.S because the formula is wrong actually the formula is (a+b)²=a²+2ab+b².

Answer 2

Step-by-step explanation:

Given: (a+b)²

To prove: (a+b)² = a² + 2ab + b²

Proof:-

(a+b)² = (a+b)(a+b)

(a+b)²=a(a+b)+b(a+b)

(a+b)² = a²+ab+ab+b²

(a+b)² = a²+2ab+b².

Hence, proved.