Odpowiedź:
Szczegółowe wyjaśnienie:
[tex]A.\ (a - 1) - (1 - (a + 1) + a)=a-1-1+(a+1)-a=-2+a+1=a-1\\\\\\B.\ a - (1 - (a - 1) - (a + 1))=a-1+(a-1)+(a+1)=a-1+a-1+a+1=3a-1\\\\\\C.\ (a + 1) - (a - (a - 1) - 1)=a+1-a+(a-1)+1=2+a-1=a+1\\\\\\D.\ 1 - (1 - (a-1) - (a + 1))=1-1+(a-1)+(a+1)=a-1+a+1=2a[/tex]