[Beginner] How to document a function without defining variables?

[Andre70]

Hello,

sorry, I have to ask some beginner questions:

1. I want to use the f'(x) notation but it seems that this is not possible. Mathcad is unhappy "variable not defined" about the f'. The function f(x) as such is defined. Is there a trick?

2. I want do document some functions without defining variables. For example "slope = (f(b)-f(a))/(b-a)". Once more Mathcad wants to force me to define b and a. But that doesn't make sense in my case since I just want to document the concept and not do an actual calculation. I use a text box with a inside calculation box to get the mathematical notifications. 

I feel deeply sorry that I have to bother you with probably very simple questions. 🙂 

Kind Regards

[DJNewman · Accepted solution]

Regarding 1, read the documentation on the prime operator: https://support.ptc.com/help/mathcad/r9.0/en/index.html#page/PTC_Mathcad_Help/derivative_and_prime_operators.html#

Regarding 2:

You can use the boolean equal sign (Ctrl + =; you can also find it in the Operators drop-down under "Comparison") to make such statements without actually having to define anything. This just serves as documentation.

[terryhendicott]

https://www.google.com/search?q=mathcad+prime+beginners+guide will bring up a beginners guide on youtube.

[LucMeekes]

Ad.2.

If you define it as a function of all parameters, you can do without error:

Then the function you want to get the slope of doesn't need to be defined beforehand:

Success!
Luc

[Andre70]

Hi guys, thank you for help.