(m - 4)^2 - (3 - m)^2 = m^2 - 2 * 4 * m + 4^2 - (3^2 - 2 * 3 * m + m^2) = m^2 - 8m + 16 - (9 - 6m + m^2) = m^2 - 8m + 16 - 9 + 6m - m^2 = -2m + 7;
m^2 - m^2 = 0;
-8m + 6m = -2m;
16 - 9 = 7.
Объяснение:
(m-4)^2-(3-m)^2=((m-4)-(3-m)(m-4)+(3-m)=
=(m-4-3+m)(m-4+3-m)≠(2m-7)(-1)=7-2m
