Упростите выражение: 1. 4c(c-2)-(c-4)² 2. 3a(a+2)-(a+3)² 3. 3(y-1)²+6y 4. 8c+4(1-c)² 5. 4ab+2(a-b)²
1. 4c(c-2)-(c-2)(c+2)=(c-2)(4c-c-2)=(c-2)(3c-2) 2. 3a(a+2)-(a+3)^2=3a^2+6a-a^2-6a-9=2a^2-9 3. 3(y^2-2y+1)+6y=3y^2-6y+3+6y=3(y^2+1) 4. 8c+4-8c+4c^2=4(1+c^2) 5. 4ab+2a^2-4ab+2b^2=2(a^2+b^2)