Finding the Solution for a Tricky ln Equation

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The equation ln(x+1) = x-3 can be transformed into e^(x-3) = x + 1. However, it is impossible to express the solution for x using elementary functions due to the presence of both transcendental and non-transcendental components. To find an approximate solution, numerical methods or graphing techniques are recommended. Specifically, one can graph y = e^x - 3 and y = x + 1 to identify their intersection point. Ultimately, an algebraic solution does not exist for this equation.
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ln (x+1) = x-3

i know ln is log base e so the equation becomes:

e^(x-3) = x + 1

and i can rearrange using algebra to get:

e^x = e^3(x+1)

but now I am stuck...how can i separate the x's to solve for it?

thanks.
 
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You can't write the solution x in terms of elementary functions like e^x and ln(x). You'll probably have to use a calculator to get an approximate numerical solution.
 
ah thanks.
 
In general, there is no "algebraic" solution for problems that involve both a transcendental function of x (such as ex) and non-transcendental function of x (such as x+1). You will have to use some approximation method (such as graphing y= ex-3 and y= x+1 and seeing where they cross).
 
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