Задание
Определите знак произведения:
| \(\displaystyle a(-b\,)={\bf -ab}\) |
| \(\displaystyle (-a\,)b={\bf -ab}\) |
| \(\displaystyle (-a\,)(-b\,)={\bf ab}\) |
| \(\displaystyle -(-a\,)={\bf a}\) |
| \(\displaystyle -((-a\,)b\,)={\bf ab}\) |
| \(\displaystyle -((-a\,)(-b\,))={\bf -ab}\) |
| \(\displaystyle -(a(-b\,))={\bf ab}\) |