For 2 bit we can find by finding exact combination
but for n bits
if we comparing n bits then
for A>B or A<B or A=B
first find equal condition and total possible cases
for A=a0a1......an and B=b0b1b2......bn
so truth table creating implies 2n variables implies total 2"2n rows implies total possible cases are 2'2n
for A=B
if we select some value for a0a1.......an then B values must be same
so for n variable we have 2'n possiblities to put values
hence for equality we have 2'n cases
for unequal it is 2'2n-2'n
and since A>B and B<A has same number of cases
so A>B=A<B=2'2n-2'n/2
