Раскройте скобки: \( -6\cdot(3m-7n\,)^2=\)?\( m^{\,2}\) ?\( mn\) ?\( n^{\, 2}\)

Задание

Раскройте скобки:

\(\displaystyle -6\cdot(3m-7n\,)^2=\)[?||-][ ]\(\displaystyle m^{\,2}\) [?|+|-][ ]\(\displaystyle mn\) [?|+|-][ ]\(\displaystyle n^{\, 2}\)