Question

Find the arithmetic mean of (m + n)² and (m – n)².

Answer 1

Arithmetic mean of (m + n)² and (m – n)²

= `((m + n)^2 + (m - n)^2)/2`

= `(m^2 + n^2 + 2mn + m^2 + n^2 - 2mn)/2`

=`(2(m^2 + n^2))/2`

= m² + n²