If the operation * is defined for all integers a and b by a*b=a+b-ab,which of the foll must be true for all integers a,b and c??
I-a*b=b*a
II-a*0=a
III-(a*b)*c=a*(b*c)
I-a*b=b*a
II-a*0=a
III-(a*b)*c=a*(b*c)
Maxx
a*b = a+b+ab
b*a = b+a+ba (ba= ab)
II is true
a*0 = a+0+0=a (any number multiplied by 0 is 0)
III is true
a*b = a+b+ab
(a*b)*c = a+b+ab+c+ca+cb+cab = a+b+c+ab+ac+bc+abc
b*c = b+c+bc
a*(b*c) = a+b+c+bc+ab+ac+abc = a+b+c+ab+ac+bc+abc
the answer would be the one that said I,II and III
which one is it???
