numer & denom oddities in MathCAD Prime9.0

[FB_10795922]

Dear all,

I'm exploring the functions:

• numer
• denom

And I've encountered the "oddities" in the joined MathCAD file (see what highlighted in pale yellow and the text; in pale blue some reference results for information)

To be honest I suspect multiple bugs...

If I'm wrong (i.e. we're not dealing with bugs...) , can someone explain me the logic under the quoted functions behavior, because I really cannot understand...

Many thanks in advance & Best Regards 

[Werner_E · Accepted solution]

The "hidden logic" is that sometimes the symbolics applies automatic simple simplifications and nominator and denominator are taken from the simplified expression:

Function 1:

Function 2:

Function 3:

Function 4

Prime 9 sheet attached

BTW, the 'logic' is not always that clear. For example