Q.

Among the relations

S={(a,b):a,bR-{0},2+ab>0} and 

T={(a,b):a,bR,a2-b2Z}                                      [2023]

1 S is transitive but T is not  
2 both S and T are symmetric  
3 neither S nor T is transitive     
4 T is symmetric but S is not  

Ans.

(4)

For relation T=a2-b2I

Then, (b,a) on relation Rb2-a2I

T is symmetric, S={(a,b):a,bR-{0},2+ab>0}

2+ab>0ab>-2ba>-12

If (b,a)S, then 2+ba is not necessarily positive.

   S is not symmetric.