Natural Logs and inverse functions

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SUMMARY

The discussion focuses on solving the equation y=(e^x)/(1+2e^x) for its inverse. The user attempts to isolate x but struggles with the term ln(1+2e^x). The solution involves multiplying both sides by (1 + 2e^x) to rearrange the equation, allowing for the factoring of e^x and simplifying the expression to isolate x effectively. The key takeaway is the importance of rearranging terms and factoring in solving for inverse functions involving natural logarithms.

PREREQUISITES
  • Understanding of natural logarithms and their properties
  • Familiarity with exponential functions and their inverses
  • Basic algebraic manipulation skills
  • Knowledge of solving equations involving multiple variables
NEXT STEPS
  • Study the properties of inverse functions in calculus
  • Learn techniques for solving exponential equations
  • Explore the application of logarithmic identities in algebra
  • Practice problems involving the manipulation of equations with natural logs
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Students studying calculus, mathematics educators, and anyone interested in mastering the manipulation of exponential and logarithmic functions.

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Homework Statement


Find the inverse equation (i.e. solve for x)
y=(e^x)/(1+2e^x)2. The attempt at a solution
e^x = y(1+2e^x)
x = ln(y) + ln(1+2e^x)
?
Profit!

I can't figure out what to do with ln(1+2e^x) to get the x out of there so I can finish isolating x. I tried balancing it another way and ended up with x = ln(e^x - y) - ln(2y) which as far as I can tell is worse. Any suggestions? As far as I can tell I'm probably just missing something obvious but I've been sitting here for a while trying to figure it out...
 
Last edited:
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Starting with y = e^x/(1 + 2e^x),
multiply both sides by (1 + 2e^x).

Get all the terms that involve e^x on one side, and all other terms on the other side.
Factor e^x out of the terms that have this factor and divide both sides by the factor that isn't e^x.
 
*facepalm* Thank you... I don't know why I couldn't figure that out...
 

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