Question

what the answer of this formula a^2+b^2=?
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Answer 1

Answer:

a2+2ab+b2=(a+b)2−−−−−i

So, a2+b2=(a+b)2−2ab

Again we know,

a2−2ab+b2=(a−b)2−−−−−ii

So, a2+b2=(a−b)2+2ab

By addition i and ii we get,

a2+2ab+b2+a2−2ab+b2=(a+b)2+(a−b)2

2(a2+b2)=(a+b)2+(a−b)2

So, a2+b2=((a+b)2+(a−b)2))/2