Question

алгебра 7 класс помогите пожалуйста ​

Answer 1

#1

$(a+8)^2=a^2+2*a*8+8^2=a^2+16a+64\\(5m-4n)^2=(5m)^2-2*5m*4n+(4n)^2=25m^2-40mn+16n^2\\(m^4-n^3)^2=(m^4)^2-2*m^3*n^3+(n^3)^2=m^8-2m^3n^3+n^6$

#2

$a^8-4a^4+4=(a^4)^2-2*a^4*2+2^2=(a^4-2)^2$

#3

$3m(m-4)-(m+2)^2=3m^2-12m-(m^2+4m+4)=3m^2-12m-m^2-4m-4=2m^2-16m-4$