XˉY+XYˉ\bar{X} Y+X \bar{Y}XˉY+XYˉ
XYˉ+XYX \bar{Y}+X YXYˉ+XY
X‾Y+XY\overline{\mathrm{X}} \mathrm{Y}+\mathrm{XY}XY+XY
X‾ Y‾+XY\overline X \space \overline Y + XYX Y+XY