# I'm new in using Matlab and I'm very confused of how I would solve a derivative problem. Here is the equations and problem

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Neil Allen le 24 Sep 2022
Commenté : Davide Masiello le 24 Sep 2022
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### Réponse acceptée

Hiro Yoshino le 24 Sep 2022
You are using the capabilities of Symbolic Math Toolbox and with this you can manupulate your equations symbolically.
Let's define your symbol x. Then the following equation y1 is also defined symbolically as follows:
syms x a
y1(x) = 1/((x+1)^3*(2*x-1)^3) + a
y1(x) =
Derivative of y1 is quite straightfoward. If you want to differentiate y1 with respect to x, diff is the one:
yp1 = diff(y1)
yp1(x) =
If you want to know the variables used in the function y1, symvar will do the work
symvar(y1)
ans =
x
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### Plus de réponses (1)

Davide Masiello le 24 Sep 2022
Modifié(e) : Davide Masiello le 24 Sep 2022
I think what you have in your snapshot is already ok. You just need to save the functions in y1, y2 and y3. There are also some errors with the brackets, check your code carefully.
syms x
y1(x) = 1/((x+1)^3*(2*x-1)^3);
y2(x) = 1/(1+sqrt(1-x))^3;
y3(x) = (x^2/(4-x))^(3/2);
yp1 = diff(y1)
yp1(x) =
yp2 = diff(y2)
yp2(x) =
yp3 = diff(y3)
yp3(x) =
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Neil Allen le 24 Sep 2022
Ohhh thank you!
Davide Masiello le 24 Sep 2022
My pleasure. Please consider that it is costumary to accept the answer if it helped, as a reference other users with the same or similar problems.

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