Question

помогите мне,умоляю

Answer 1

10) = (a²-b²)(a²+b²)=a^4-b^4
11) = c(c²-4)-(c³-1)=c³-4c-c³+1= -4c+1
12) = 2(x+y)-(x²+2xy+y²)=2(x+y)-(x+y)²=(x+y)(2-(x+y))=(x+y)(2-x-y)