Logarithms in Systems of Equations

AI Thread Summary
The discussion centers on solving the system of equations y=e^{-x}+1 and y=2+lnx. The initial approach involved finding the intersection point of the graphs, yielding a numerical solution of approximately (0.627, 1.534). Participants note that there is no straightforward algebraic method for solving this system, as many equations lack a neat analytical solution. While some specific equations can be solved easily, the general case often requires numerical methods. Overall, the consensus is that a purely algebraic solution is unlikely to exist for this system.
Mandelbroth
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Homework Statement


Consider the system...

y=e^{-x}+1 \\ y=2+lnx

The Attempt at a Solution


I don't think there is a "pretty way" (algebraic manipulation) to do this. I simply found the point where the plots intercepted, getting the solution set (0.62745018..., 1.5339409...).

Is there a better way to do this? For what it's worth, this was for a friend who claims that her math teacher is unreasonable, so I don't know if it does has a fully algebraic approach.

Edit: For clarity, both have a domain and codomain in the set of real numbers, so there isn't an imaginary part to worry about.
 
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Mandelbroth said:
Is there a better way to do this?
In general, there is not. Some equations have an analytic solution which is easy to find (x+e^x = 1 for example), but the general case does not have a nice solution.
 
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