Question

si 0
a. (m+n)^2 > m^2 + n^2

b. (m-n)^2 < (m+n)^2

alguien me puede explicar por favor!!

Answer 1

m^2 + 2mn +n^2 > m^2 + n^2
2mn > 0
mn > 0


m^2 - 2mn + n^2 < m^2 + 2mn + n^2
-2mn < 2mn
0 < 4mn
4mn > 0
mn > 0