Раскройте скобки: 1) (a – b) + (c – d) 2)- (-a + b) – (- c – d) 3) (a + b) – (c + d) 4) –(a + b) + (- c – d) 5) – (a

Решение.

1) (a – b) + (c – d) = a – b + c – d;

2) - ( - a + b) – ( - c – d) = a – b + c + d;

3) (a + b) – (c + d) = a + b – c – d;

4) –(a + b) + ( - c – d) = - a – b – c – d;

5) – (a – b) – (c + d) = - a + b – c – d;

6) (a – b) - (c – d) = a – b – c + d;

7) - ( - a - b) + (- c – d) = a + b – c – d;

8) (a + b) + ( - c + d) = a + b – c + d;

9) – (a - b) + (-c – d) = - a + b – c – d;

10) – (a + b) – (c + d) = - a – b – c – d.