Determine whether ababc where c is at most ab and abba are c
Determine whether a*b=a^b+c (where c is at most a^b) and a*b=b^a are commutative and/or associative.
Determine whether the definition of * gives a binary operation on the set. If * gives a binary operation on the set, then determine whether * is commutative and whether * is associative. the operation * defined on Z^+ by a * b = a^b + c, where c is at most a^b the operation * defined on Z^+ by a * b = b^aSolution
commutative law is as follows
example + operator
2+3=3+2=5
and associative law can be proved by
2+(3+4)=(2+3) +4 = 9
1) a*b=ab+c
now b*a= ba + c which is not equal to a*b
Hence not follows commutative law
a*(b*c) =a*(bc+k)= ab^c+k+g
(a*b)*c=(ab+d)*c=((ab+d)^c + k
Hence not follows associative law
2) a*b=ba and b*a=ab hence not follows commutative law
(a*b)*c=ba*c= cb^a
a*(b*c)= a*cb=(cb)^a=cba Hence not follows associative law
