Show that * on R –{ - 1}, defined by 
is neither commutative nor associative.
let a = 1,b = 0
R - { - 1}
a*b = 
= 1
And b*a = 
= 0
Hence * is not commutative.
Let c = 3.
(a*b)*c = 1*c = 
a*(b*c) = a*
= 1*0 = 
= 1
Hence * is not associative.
1
Show that * on R –{ - 1}, defined by is neither commutative nor associative.
let a = 1,b = 0R - { - 1}
a*b = = 1
And b*a = = 0
Hence * is not commutative.
Let c = 3.
(a*b)*c = 1*c =
a*(b*c) = a* = 1*0 = = 1
Hence * is not associative.