Question

(a-b)²-(a+b).(a-b) simplifique a expressao

Answer 1

(a-b)2-(a+b)(a-b)
 = (a-b)(a-b) - (a+b)(a-b)
 = (a$^{2}$-2ab+b$^{2}$)- (a$^{2}$-b$^{2}$)
= a$^{2}$-2ab+b$^{2}$-a$^{2}$+b$^{2}$      (simplificando a$^{2}$   e   –a$^{2}$ ) teremos:
 = -2ab+b$^{2}$
 = 2(-ab+b$^{2}$)