Salutare!
[tex]\bf 1-(1996\cdot 1997+1997):1997^{2} =[/tex]
[tex]\bf 1-1997\cdot( 1996+1):1997^{2} =[/tex]
[tex]\bf 1-1997\cdot 1997 : 1997^{2} =[/tex]
[tex]\bf 1-1997^{2} : 1997^{2} =[/tex]
[tex]\bf 1-1997^{2-2}=[/tex]
[tex]\bf 1-1997^{0}=[/tex]
[tex]\bf 1-1=[/tex]
[tex]\boxed{\bf 0}[/tex]
