function numden:
The function numden will return individually the numerator & denominator of a symbolic expression:
>> sym(1/3 + 1/2)
ans =
5/6
>> [n, d] = numden(ans)
n =
5
d =
6
>> [n, d] = numden((x^3 + x^2)/x)
x^2*(x 1)
x