Solving Coefficien​ts for Non-Linear Equation

I have the following equation that I need to solve a, b and c. y = a+bexp(-x/c). Is there a VI that is written to help me?

i don't understand what do you suppose to mean?
you have not a,b and c values and you wanna solve 3 unknown variables with just one equation?
do you think is that possible?
even you had x and y values!
but if you have 4 values and you just want to find another variables value it's so easy
you can easily use a formula node.
i have write a simple program for you to solve this equation and i attached it to this answer.
it's with LabVIEW 5.
Attachments:
formula_node_example.vi ‏25 KB

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