Question

как решить этот пример? 5×(m+n)^2-m×(10n+m)-n^2=

Answer 1

5×(m+n)^2-m×(10n+m)-n^2=5*(m^2+2mn+n^2)-10mn-m^2-n^2=5m^2+10mn+5n^2-10mn-m^2-n^2=4m^2+4n^2

Answer 2

5×(m^2+2mn+n^2)-10mn-m^2-n^2=5m^2+10mn+5n^2-10mn-m^2-n^2=4m^2+4n^2