Assigning a variable to a result of a "series" symbolic operation

[DK_9691716]

I want to put the result in a variable f.1(x), but the mathcad says that this variable is undefined. The only way that works is to assign by-hand (as seen below) but i would like to know about more clever solution

[Werner_E]

What you did should work and it actually does:

But without seeing your sheet its quite difficult to guess what could be wrong.

P.S.: I noticed the the result of the symbolic evaluation looks different in your pic (while being mathematically the same). Especially the factor 1 are somewhat irritating as Mathcad usually doesn't do this - even if you don't tell it to simplify.

Which version and maintenance release of Mathcad are you using?

MC15(M050) sheet attached

[LucMeekes]

Looks like a Maple result. I guess Mathcad 11, 12 or 13:

Luc

[Werner_E]

Ah, quite possible.

But nonetheless the assignment should work OK, shouldn't it?

[LucMeekes]

Agreed!

I tried a few illegal constructs, but didn't find the one that only marks (or appears to mark) the x argument red. Maybe 12 or 13 react differently from 11...

Guess we won't know until the OP attaches the worksheet.

Luc