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Răspuns:
E(x) = E(1)
E(1) = 1³+1-2 = 0=> E(x) = 0
E(-1) = (-1)³+3(-1)²+5(-1)+3 = -1+3-5+3=6-6=0 => E(x) = E(-1) =0
E(½) = 2x(½)³+(½)²+(½)-1 = 2x⅛+¼+½-1=¼+¼+½-1=½+½-1=1-1=0 =>E(x)=0
E(2) = 2³+2²-2x2-8=8+4-4-8=0=> E(x) =0