a)
23-[(-3)+(+5)-(-7)]-(-11)=
23-(-3+5+7)+11=
23-9+11=
14+11=
25
b)
5-2•[(-12):3]²+[(-2)³]²=
5-2•(-4)²+(-2)^6=
5-2•16+2^6=
5-32+64=
69-32=
37
c)
-2-4-6-...-2000=
-1(2+4+6+....+2000)=
-1[(2002•1000)/2]=
-1(1001•1000)=
-1•1001000=
-1001000
d)
4563•34-4563•200+166•4563=
4563(34-200+166)=
4563(200-200)=
4563•0=
0