Question

1) (x-8)^2-2x(6-x)^2
2) (c+7)c-(1-c)^2
3) 2(a-b)^2

Answer 1

1) (х-8)(х-8)-2х(6-х)(6-х)=х²-16х+64-2х(36-12х+х²)=х²-16х+64-72х+24х²-2х³=25x²-88x+64-2x³
2) (с+7)с-(1-с)(1-с)=с²+7с-1+2с-с²=9с-1
3) 2(а-b)(a-b)=2(a²-2ab+b²)=2a²-4ab+b²