Inverse Function of g(x) at 4 - Solve Algebraically

AI Thread Summary
To find the inverse of g(x) = 3 + x + e^x at 4, the equation simplifies to 1 = x + e^x. The discussion highlights that there is no algebraic solution using elementary functions for this equation. Instead, numerical methods are required to approximate the solution, with x = 0 being a plausible initial guess. A graphical approach confirms that there is only one solution to the equation. Ultimately, the problem illustrates the limitations of algebraic methods in solving certain transcendental equations.
Miike012
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Problem: If g(x) = 3 + x + e^x find Inverse of g at 4

My work:

4 = 3 + x + e^x
1 = x + e^x

This is where I stop... I can look at it and see that x = 0
But I don't know how to find the solution algebraically...
 
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You can't find the solution algebraically, you'll need to use numerical methods.
 
Miike012 said:
Problem: If g(x) = 3 + x + e^x find Inverse of g at 4

My work:

4 = 3 + x + e^x
1 = x + e^x

This is where I stop... I can look at it and see that x = 0
But I don't know how to find the solution algebraically...

On the one set of axes draw a sketch of y=e^x and y=1-x and see that there's only the one solution. So your initial guess is it.

There is no algebraic solution in terms of elementary functions. So your "look at it" method is as good as any.
 
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