Question

выполните действие:2с(с-b)-(c-3)(c+3)

Answer 1

2c(c-b)-(c-3)(c+3)=2c^2-2cb-(c^2-9)=2c^2-2cb-c^2+9=c^2-2cb+9

Answer 2

2с2-2CB-(c2-9)= 2с2-2cb-c2+9=c2-2cb+9