ajutati maaaaaaaaaa.....
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a)
E(-1)=|-1|/1=1/1=1
E(1)=|1|/1=1/1=1
b)
E(-n)=|-n|/n=(+/-)n/n=1 dc n>0 si -1 dc n<0
E(n)=|n|/n=n/n=1
c)
E(2)+E(-3)+...+E(-101)=1-1+1-1+...+1-1=0