cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
Showing results for 
Search instead for 
Did you mean: 

Community Tip - Need to share some code when posting a question or reply? Make sure to use the "Insert code sample" menu option. Learn more! X

How do you solve an equation for a term that isnt a single variable?

RK_12705188
2-Explorer

How do you solve an equation for a term that isnt a single variable?

I want to solve the following equation at the bottom and get T_react/T_com on one side and the rest on the other side. Is there a way to rearrange the equation like that?

 

I am using Version 10.0.1.0

 

MathCADForum.png

ACCEPTED SOLUTION

Accepted Solutions
Werner_E
25-Diamond I
(To:RK_12705188)

How about

Werner_E_0-1736425906188.png

 

Prime 10 sheet attached

 

View solution in original post

6 REPLIES 6
LucMeekes
23-Emerald III
(To:RK_12705188)

Welcome to the forum.

You should attach your worksheet and state which version of Prime you are using.

 

To answer your question:

Solve for the two variables (make sure you have two independent equations then), or define a single variable e.g. Tratio, and solve for that.

 

Note that the solve you display doesn't work because Treact and Tcom are not part of the equation Tmot-Tfrict.

If you want to use something like this, you have to define Tmot and Tfrict as functions of Treact and Tcom (and that ripples through to the beginning of your definitions.

 

Success!
Luc

Thanks for the reply. I added the worksheet with the MathCAD Prime Version 10.0.1.0.

I tried implementing your solution, but I don't fully understand what you mean. I used Tratio as a variable for Tmot and Tfrict and tried to solve Tmot-Tfrict for Tratio, which isn't working,

LucMeekes
23-Emerald III
(To:RK_12705188)

You defined Tmot(Tratio) , but Tratio does not appear to the right of the definition symbol, so it is actually not a function of Tratio.

You have more work to do. I think you would be better off with two equations, like this:

LucMeekes_1-1736418633151.png

Note that I would rather do this like:

LucMeekes_3-1736418737333.png

 

But I cannot decide what the right equations would be for your problem.

 

Success!

Luc

It seems like I didn't ask my question the right way. The shape of the solution I want is the following:

RK_12705188_0-1736419404338.png

So the term Treact=Tmot-Tcom rearranged as a transfer function for a control loop.

With two equations I would get two solutions (Tcom and Treact), which isnt my goal. Or am I misinterpreting your answer?

Werner_E
25-Diamond I
(To:RK_12705188)

How about

Werner_E_0-1736425906188.png

 

Prime 10 sheet attached

 

Thanks alot, that is exactly what I wanted!

Announcements

Top Tags