Question 1084185
your set is {1,2,3}


one possible subset is {1,2,3}


that is called an improper subset.


in general, every set is an improper subset of itself.


the other possible subsets are:


{1}
{2}
{3}
{1,2}
{1,3}
{2,3}


they are called proper subsets because the super set {1,2,3} contains at least 1 element that is not within the sub set.


therefore, all possible subsets of {1,2,3} are:


{1}
{2}
{3}
{1,2}
{1,3}
{2,3}
{1,2,3}


they include all proper subsets plus the improper subset of {1,2,3}.