get popupmenu ("^A ,^B ,^C ,^D ,",0, the mouseH, the mouseV )
if it is empty then exit to HyperCard
put it into choice
get choice + 272
-- This sets the helper button so people can remember the variables
show btn "Variable helper"
set the icon of btn "variable helper" to it
ask "What is the multiplicative constant..b ?" with 1
if it is empty then exit to HyperCard
put it into b
put line choice of table into root
if root is empty then
ask "what is the root…a ?"
if it is empty then exit to HyperCard
put it into root
end if
if choice is 2 then
put b & " * " & "exp(x)" into fld function
else
if choice is 4 then
ask "What is the constant…c ?"
put b & " * " & root & "^(" & it & " * x)" into fld function
else
put b & " * " & root & "^x" into fld function
end if
end if
hide btn "Variable helper"
end mouseDown
-- part 2 (button)
-- low flags: 80
-- high flags: 4004
-- rect: left=205 top=60 right=98 bottom=302
-- title width / last selected line: 0
-- icon id / first selected line: 274 / 274
-- text alignment: 1
-- font id: 0
-- text size: 12
-- style flags: 0
-- line height: 16
-- part name: Variable helper
-- part contents for background part 4
----- text -----
Exponential Function Editor
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----- text -----
Use this card to form the exponential functions that you'd like to see graphed. You can use the function editor to change the general form of the exponential to what you want by setting the values of the variables.
If you'd like to read more, click this button -->
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----- text -----
Exponential Edit Box
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----- text -----
Exponential Functions
Aexp(bx)
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----- text -----
In a very basic sense an exponent is a superscripted number above and to the right of another number. The symbol that this stack uses to internally represent an exponent is the ^.
An exponential function is a function that returns the value of some number to the x power. For example
f(x) = 10^x would return 10 raised to whatever x was. Using that example f(1) = 10, f(2) = 100,
f(3) = 1000 etc. An important thing to realize is that x doesn't have to be a counting number. It could be a number like 1/7 or -4.23.
In the pull down menu there are some premade functions for you. Two of the forms will require that you supply the values of the root…a. The other two forms have already suppled the root of the exponential
function. These numbers are common forms of exponentials and they are 10 and e. The number e is an irrational number. Such a number can be represented as a non-repeating, non-ending decimal. The number e is approximately equal to 2.718281828459045235.
Exponentials are an integral part of many branches of science and mathematics. They are often used to compute things like radioactive decay, growth of bacteria, and charge in a circuit.
