Упростите:
(a+b-c)^2-(a-b-c)^2
(a+b-c)^2-(a-b-c)^2 = ((a+b-c)-(a-b-c))((a+b-c) + (a-b-c))= (a+b-c-a+b+c)(a+b-c + a-b-c)= b^2 * a^2