How Can You Solve the Equation e^x = 5-2x?

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SUMMARY

The equation e^x = 5 - 2x can be solved using numerical methods or the Lambert W function, which is the inverse of the function f(x) = x * e^x. The discussion emphasizes that traditional algebraic methods are ineffective due to the presence of x in both the exponent and as a linear term. A graphical approach is recommended for approximating the solution, particularly through methods like decimal search for finding intercepts. This approach is suitable when high accuracy is not required.

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I am a little stuck how to solve this equation

e^x = 5-2x?

I did ln e^x = ln (5-2x)

x = ln(5-2x) / ln e
but iam not sure how to bring the other x around to the side with the x to solve the equation?
 
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You can't with the "usual" functions. Since you have x both in the exponent and not, you would have to do a numerical solution or use "Lambert's W function", the inverse function to f(x)= xex.
 
how would you go about doing a numerical solution?
 
Why not try it graphically and then do some approximating to find the intercept, e.g. decimal search. This would work if you did not need a highly accurate solution, e.g. in terms of Pi.

The Bob (2004 ©)
 

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