A={x ϵ" role="presentation" style="font-size: 13.696px; display: inline; word-spacing: 0px; font-family: Arial, 'Liberation Sans', 'DejaVu Sans', sans-serif; position: relative;">ϵϵ N l0≤" role="presentation" style="font-size: 13.696px; display: inline; word-spacing: 0px; font-family: Arial, 'Liberation Sans', 'DejaVu Sans', sans-serif; position: relative;">≤≤ x ≤" role="presentation" style="font-size: 13.696px; display: inline; word-spacing: 0px; font-family: Arial, 'Liberation Sans', 'DejaVu Sans', sans-serif; position: relative;">≤≤ 100}
A={x $\epsilon$ N l 0$\leq$ x $\leq$ 100 và x chia hết cho 5}