SOLUTION: what's the reciprocal function of f(x)= (4e^x)/(3+5e^x)

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Question 1069474: what's the reciprocal function of f(x)= (4e^x)/(3+5e^x)
Answer by htmentor(1343) About Me  (Show Source):
You can put this solution on YOUR website!
The reciprocal, or inverse function, is found by first solving y = 4e^x/(3+5e^x) for x. You should obtain the following equation. x = ln(3y/(4-5y))
Now reverse x and y:
y = ln(3x/(4-5x)) = f_inv(x)
If we plot the two functions, we see that they are reflections of each other about the line y=x: