@Mayankprakash
find the minimal i.e. i,j,m then see the diagram again which element is at the lowest level among i,j and m ?
its m ,...so m is the minimum element.
rotate the daigram by 180 and repeat the above step to get the maximum element.
NOTE :- if there are 2 or more elemenet at the lowest level then neither of them will be maximum or minimum element because there can be only 1 maximum and 1 minimum element in a poset.
GLB(meet) and LUB(join) are done wrt to a subset of the poset.
Suppose we take the set {g,h} and then calculate the Join and meet for it.
Put a ball at g and another at h and let them roll downwards. what are the points at which they meet ?
j and m
where they will meet early at j or at m ? j right ? so j will be meet.
Flip the daigram and do it for getting join
we will get a,d,e,b. but where are they meeting early ?
at d or at e so there is not a join possible
NOTE:- there is only 1 meet and 1 join for a given subset of the poset.
