First of all, any number to the 0 power
is just one so replace the  by .



which amounts to just erasing it:



Next we get rid of all negative exponents by this
pair of rules:

If any factor of the numerator has a negative exponent,
then move it from the numerator to the denominator and
change the sign of the exponent to positive:

If any factor of the denominator has a negative exponent,
then move it from the denominator to the numerator and
change the sign of the exponent to positive:



We move the  from the numerator to the 
denominator and write it with a positive exponent
 in the denominator:



Next we move the  from the denominator to the 
numerator and write it with a positive exponent
 in the numerator:



Finally we add the exponents of  in the numerator
and we end up with:



Edwin