Vba function problem

[zaneta0709]

I don't know what i did wrong but when I'm trying to use those two Functions they are not running.

Here is my exercise :

And this is my vba function :

 

[Peter_SSs]

Welcome to the MrExcel board!

And this is my vba function :

It would help in future if you post your actual code rather than an image of it so that we can copy for testing. My signature block below has more on that.

As far as I can see, your issues are ..
antoine: Your function has t multiplied by C when they should be added
medication: e is the constant 2.718... not a variable input. In vba use the Exp() function for that.

So, try these

Function antoine(A As Double, B As Double, C As Double, t As Double) As Double
  antoine = 10 ^ (A - B / (t + C))
End Function

Function medication(C0 As Double, k As Double, t As Double) As Double
  medication = C0 * Exp(-(k * t))
End Function

Checks

zaneta0709.xlsm
	A	B	C	D	E
1	antoine	A	B	C	t
2	416.5845392	8.08097	1582.271	239.726	50
3
4	medication	C0	k	t
5	27.06705665	200	0.5	4
Sheet1

Cell Formulas
Range	Formula
A2	A2	=antoine(B2,C2,D2,E2)
A5	A5	=medication(B5,C5,D5)

 

[RoryA]

Welcome to the forum.

What exactly do you mean by "not running"? What is happening specifically?

 

[RoryA]

Also:

Cross-posting (posting the same question in more than one forum) is not against our rules, but the method of doing so is covered by #13 of the Forum Rules.

Be sure to follow & read the link at the end of the rule too!

Cross posted at: Vba function problem
If you have posted the question at more places, please provide links to those as well.

If you do cross-post in the future and also provide links, then there shouldn’t be a problem.

 

[zaneta0709]

Welcome to the MrExcel board!


It would help in future if you post your actual code rather than an image of it so that we can copy for testing. My signature block below has more on that.

As far as I can see, your issues are ..
antoine: Your function has t multiplied by C when they should be added
medication: e is the constant 2.718... not a variable input. In vba use the Exp() function for that.

So, try these

Function antoine(A As Double, B As Double, C As Double, t As Double) As Double
  antoine = 10 ^ (A - B / (t + C))
End Function

Function medication(C0 As Double, k As Double, t As Double) As Double
  medication = C0 * Exp(-(k * t))
End Function

Checks

zaneta0709.xlsm
	A	B	C	D	E
1	antoine	A	B	C	t
2	416.5845392	8.08097	1582.271	239.726	50
3
4	medication	C0	k	t
5	27.06705665	200	0.5	4
Sheet1

Cell Formulas
Range	Formula
A2	A2	=antoine(B2,C2,D2,E2)
A5	A5	=medication(B5,C5,D5)

Thank you so much that solved my problem

 

[Peter_SSs]

Thank you so much that solved my problem

Actually, since A, B & C in antoine are also constants, probably best if you include them in the function directly.
Edit: Posting too fast & missed the instruction about including those constants as arguments. I assume they are different constant values in different circumstances.

And a very minor point - you have an extra set of parentheses in the medication function that is not needed.

So slight refinements:

Function antoine(t As Double) As Double
  antoine = 10 ^ (8.08097 - 1582.271 / (t + 239.726))
End Function

Function medication(C0 As Double, k As Double, t As Double) As Double
  medication = C0 * Exp(-k * t)
End Function

zaneta0709.xlsm
	A	B	C	D
1	antoine	t
2	416.5845392	50
3
4	medication	C0	k	t
5	27.06705665	200	0.5	4
Sheet1

Cell Formulas
Range	Formula
A2	A2	=antoine(B2)
A5	A5	=medication(B5,C5,D5)