Question

simplificar  (x-y)²-(x+y)²

Answer 1

$(x-y)^{2} - (x+y)^{2} \\ \\ x^{2} + y^{2} -2xy - (x^{2} + y^{2} +2xy) \\ \\ x^{2} + y^{2} -2xy - x^{2} - y^{2} -2xy \\ \\ -4xy$

Saludos