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I wish to define a function which is the derivative of another function.

> f:=(x)->x^2:

> g:=(x)->diff(f(x),x):

> g(x);

2 x

> f(2);


> g(2);
Error, (in g) invalid input: diff received 2, which is not valid for its 2nd argument


I cannot find a way in which I can define the function g, using the functional operator, so that I can actually evaluate g(x).


How can I do this?


I have this function:

Z := (cos((1/2)*x)-I*sin((1/2)*x))*A0/r^(1/2)+(cos((1/2)*x)+I*sin((1/2)*x))*r^(1/2)*A1+(cos(3*x*(1/2))+I*sin(3*x*(1/2)))*r^(3/2)*A2;

I wanna to obtain another function Y which equal to


where: f1 and f2 are constant 

thanks :)

how are iterated functions represented in maple? as in f(f(f(x))) is f^3(x)(x)  in conventional notation where by the reader knows it is refering to the iteration conducted 3 times on the argument x, but what does maple use to differentiate between iteration ,exponentiation and differentiation?

Having a function where the value is for example only defined when abs(x) <= 1, then how can I specify that the value is otherwise undefined, the replacing "How_to_specify_undefined_value" below?

Below I want to explore a function behaviour using a slider to determine the value of 'a' so the function is shown in a plot, but I can't figure out how to use Explore to bind the value of 'a'.

If I bind bind the value using "a := 5", then plot works, but when binding through Explore it does not work.  I can also write the function in the plot like "a * x", but that is not as general as using a function.

How to explore function like that.



Let, fixed an integer i and 1<=j<=2^{i}-1, for each x and y in [0,1] let the following mapping

Then, with the above procedure we can obtained, for a fixed i, all the mappings for j=1,...,2^{i}-1


However, How can I to evalute the "components" of the above procedure? For instance, I can not to compute CreaF(2)[1](0.35,0.465) (i.e., the first function in the "vector" CreaF(2), in x=0.35, y=0.465). 


Thanks very much for your time.


Doing the following:

Why is int used when defining F not evaluated to x^2/2 when used to defined function F as shown in (2), when the int is evaluated when used separately in (3)?

I am examining the curve given by


When I put this in and assign a number to any one variable, Maple always returns



I have tried changing the names of the variables, unnassigning variables, restarting Maple, etc. but I cannot plot a function of y with x, I always get y=0.8660254038, even with only one variable assigned to a value.  I am using the student version of Maple 17.





say I have defined some (very simple, acting on a finite set M) functions f,g,h. I want to evaluate certain permutations, so I want to make a for loop that goes through possible combinations of functions in my array A=Array([f,g,h]). (In reality my array is a little larger.) No I don't understand how I can use the elements of this array as actual functions. Even if f is defined and I can evaluate, say, f(m), I cannot use A(1)(m) to evaluate m. The output is just "f(m)". How can I make maple recognize that we are having a function here?


Thanks it advance.


In the creation of a list, I would like to use the assume function twice.

Here it is a print screen of my issue.

The second part of the list is not taken into account.

Do you have ideas so that my list takes into account the second term ?

Thanks a lot for your feedback

Hello! Hope everything fine with you. Please share the command to find the max and min values of the attached function, I had tried but I was only for one variable. I am waiting your quick response.


Mob #: 0086-13001903838


I have this list :

I would like to create this list automatically:


In other words, how can I remove the 3 characters "(t)" and replace it by "_"

Do you have ideas to do so ?

Thanks a lot for your help

Suppose I have a function like this: f=cos(2t/m)+cos(2(t+5)/m).


Now for each fixed m, we get the maximum value of f. Then I want to build a plot where x-axis is m and y-axis is f, how could I do that? Please help!


I am wondering why Maple does this.

> f:=x^2
> f(3)
output: x(3)^2

I understand the difference between an expression and a function. If f is an expression, shouldn't it ouput  x^2(3). Why is the output x(3)^2?

When I enter f*3 or f*(3) then I get the correct expression.

Here is a screenshot.

Here is image inserted with a slightly different function


Also while I am here, what exactly does g(x):= x^2 do? when i enter g(3) I get g(3) back.

g(x) is neither a function nor an expression.


Consider, say, the following third order derivative:

expr := diff(f(x,y),x,y$2);

Does there in Maple exist some built-in functions for extracting from such an expression 1.) the function being differentiated, and 2.) the coordinates being differentiated with respect to? Using op(expr) is of no immediate avail as it returns only a second order derivative (as the first operand), and one of the coordinates being differentiated with respect to (as the second operand).

It is, of course, possible to make ones own function for extracting these two quantities, a crude example being

splitDeriv := proc(expr,coords::expects(list) := [])
   if PDETools:-difforder(expr) > 0 then
   end if
end proc:

for which


But it would be much nicer to use built-in functions. And perhaps such functions do exist. If so, I am unable to locate them. Perhaps I am just being stupid, for the problem seems rather elementary.

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