(a number)^to the 'A' power, divided by (the same number)^to the 'B' power =
(the same number)^(A - B) power
If 'A' = 'B', then the numerator and the denominator are both
(the same number)^to the same power,
and since (A - B = 0) , the quotient is (the same number)^to the ( 0 ) power.
But a fraction with the same thing in the numerator and the denominator is '1 '.
qed
