Variables a & h are acting like text and not numbers because a+h is
concatenating, not adding. It has to do with the Dim statement for those
variables:
Dim a, b, h, k, l As Double
Each variable must be given a type or Excel assumes type variant. Therefore
a, b, h, and k are variants, only l is Double. You cannot make a list of
variables a type with only one As Double. ie:
Dim a As Double, b As Double, h As Double,....etc.

Once you have the variables Dimmed correctly, it should work as expected.
The variable will now use the Value of InputBox instead of the Text. Text is
the default result of Inputbox, so a Variant variable would be assigned a
text.
I also notice that the variable i is not declared at all, so it also is type
Variant. I suggest the use of Option Explicit to help avoid errors with
variables.
Dim i As Long

Mike F
"Merike" wrote in message
...
Here it comes:

Sub Algandmed()
Dim a, b, h, k, l As Double
Dim tekst1, tekst2 As String
a = InputBox("Algandmete sisestamine:... Anna muutuja x
algväärtus")
b = InputBox("Algandmete sisestamine:... Anna muutuja x suurim
võimalik väärtus")
h = InputBox("Algandmete sisestamine:... Anna samm h, millega x
muutub")

tekst1 = "Sellise x-i algväärtuse korral ei ole" & Chr(13) &
"funktsioon määratud!"
k = Atn(a) * Sin(5 * a)
l = a
Cells(2, "C") = "x1="
Cells(2, "D") = a
Cells(2, "E") = "y1="
If k <= 0 Or l < 0 Then
Cells(2, "F") = "väärtus puudub"
MsgBox (tekst1)
Else
Cells(2, "F") = Log(Atn(a) * Sin(5 * a)) / Log(Cells(3, "L")) +
Sqr(3 * a ^ 3)
End If

i = 1
Do While a < b
i = i + 1
Cells(i + 1, "C") = "x" & i & "="
a = a + h
Cells(i + 1, "D") = a
Cells(i + 1, "E") = "y" & i & "="
k = Atn(a) * Sin(5 * a)
l = a
tekst2 = "x väärtuse: " & Cells(i + 1, "D") & " korral ei ole
funktsioon määratud!"
If k <= 0 Or l < 0 Then
Cells(i + 1, "F") = "väärtus puudub"
MsgBox (tekst2)
Else
Cells(i + 1, "F") = Log(Atn(a) * Sin(5 * a)) / Log(Cells(3,
"L")) + Sqr(3 * a ^ 3)
End If
Loop

End Sub


--
You can't know everything about everything.


"Mike Fogleman" kirjutas:

I am not getting that result with Excel 2000. I am getting 2, as you wish
to
get. Could you post your entire sub so we could see it?
"Merike" wrote in message
...
In my macro a=1 and h=1
And when I put
Cells(i + 1, "D") = a+h
then it writes 11 in the cell?

But it should write 2. I'm using 2000 version.
--
You can't know everything about everything.