get popupmenu ("A ln [Bx] ,A log [Bx],",0, the mouseH, the mouseV )
put "ln,log" into func
if it is empty then exit to HyperCard
put it into choice
show btn id 3
if choice is 1 then
put "A " & item 1 of func & "[Bx]" into You
set the name of cd btn id 3 to You
show btn id 3
ask "What is the constant…A?" with 1
if it is empty then exit to HyperCard
put it into A
ask "What is the constant…B?" with 1
if it is empty then exit to HyperCard
put it into B
else
put "A " & item 2 of func & "[Bx]" into You
set the name of cd btn id 3 to You
show btn id 3
ask "What is the constant…A?" with 1
if it is empty then exit to HyperCard
put it into A
ask "What is the constant…B?" with 1
if it is empty then exit to HyperCard
put it into B
end if
hide btn id 3
put A && "*" && item choice of func && "(" & B && "* x)" into fld "function"
end mouseDown
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-- part name: A ln[Bx]
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Logarithmic Function Editor
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You can use this card to edit and write the log function you wish to be graphed. Use the "Function Editor" button or enter your equation directly below. Use the "Graph Equation" button to actually graph your work.
If you'd like to read more, click this button -->
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Log Edit Box
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Logarithmic Functions
Alog(Bx), Aln(Bx)
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A Logarithm can be thought of as the inside out of an exponential. In mathematical language the logarithm is said to be the inverse of the exponential. Of course the exponential is also the inverse of the logarithm. Here's how it works:
Suppose we look at 10 squared. The mac would understand this as 10^2. People understand it as 10 X 10. Of course the answer is 100. What we have done is taken ten and multiplied it by itself two times. The result is one-hundred. We could also look at the number 100 and ask how many times ten must be multiplied by itself to get 100. The answer is 2. Ten must be multiplied by itself 3 times to get 1,000. It must be multiplied by itself 6 times to get 1,000,000. These results are better seen with the numbers than with these words. Take a look below:
This log(x) is based on the number 10. Another common logarithim is based on the number e. it is symbolized as ln(x). See the help section on the Exponential card for an explanation of that number.
One important thing to know about logarithims is that they can only work on positive numbers. Zero and negative numbers are not "legal" numbers. Click anywhere to dismiss this help section.
