Maximize and Minimize issue in Mathcad Prime

[jrodriguez-9]

Hi I have the following graph functions. However I want to get the maximum f(e) value but I do not know how to do it.

How do you obtain Maximum value and minimum values of f (y axis value) and e (x axis value) respectively. same for minimum value.

And how can you do this within a specified range. I tried to do this but it does not work.

[jrodriguez-9]

[jrodriguez-9]

I only want to get a single value. I do not know why I get a matrix.

[Fred_Kohlhepp]

your strain is a range variable. So you get an answer for each "guess".

[jrodriguez-9]

Thank you for your answer. But this does not make any sense. I am only looking for 1 value of strain e and one value of the corresponding stress f.

If I put max(f,e)= Shoulnd't I get the maximum of this value? or better yet if I put maximize(f,e,a,b)  being a and b the x axis ranges then I do not understand why this is not working.

Me having to guess from a range makes it a little tedious.

[LucMeekes]

I suppose you know the functions that describe your graphs. Finding (local) extrema is simple:

Success!
Luc

[jrodriguez-9]

Here is the Mathcad function. Want to be able to determine f and e in a simplistic way.

[Fred_Kohlhepp]

I can't open your sheet (I'm using 3.0.)

Define your function using a "guessed" variable:

When I put a range variable into me sheet I got the same number of answers as I had guesses:

Because xy was defined as a range variable there are 101 values in it; maximize found the maximum 101 times.

[jrodriguez-9]

This is the function.

[jrodriguez-9]

I guess there is no way to determine max of f for e and f values In one simple command like : max value?

[RichardJ]

You have already been told how to do it. Use the maximize function. Use a single guess value, not a range variable.

[jrodriguez-9]

ok I still feel that there is something missing here. If I use the guess value I will obtain maximum of only the value of x (strain). How can I find the corresponding f for that particular x (strain) value? I am looking for that command.

[Fred_Kohlhepp · Accepted solution]

Read this carefully:

Once you have determined the value of the variable where the maximum occurs, simply evaluate the function for that value.

[jrodriguez-9]

Thank you very much for your explanation. It has helped me understand now. I initially thought I could find a single command like max or min of (f,x,a,b) and get the values right away. But Now I understand that Mathcad Prime does not work this way as simple but you have to follow your explanation to find that particular guess value and then back-substitute it into the equation in order to obtain that particular value of f. I wanted to simplify as much as possible my calculation but now I realize this is the only way to do it.

[jrodriguez-9]

This can not be done with Minimize? I tried using Minimize but it does not work. Do you know how to do it with Minimize? or there is no such function in Mathcad Prime except for Maximize? Once again thank you.

[RichardJ]

Minimize finds minima, Maximize finds maxima. So if you want to find a maximum, use maximize.

[Fred_Kohlhepp]

Your answers:

[jrodriguez-9]

Thank you very much for your help. You are amazing. Very much appreciated.

[LucMeekes]

And if you ever wondered what the exact answer is:

Success!
Luc

[jrodriguez-9]

Not only finding maximum or minimum values but which will it be a command that for a specific strain e I can find its corresponding f? thank you all for your assistance.