What is the Inverse of a Cubic Function?

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SUMMARY

The inverse of the cubic function f(x) = ln(x^3 - 3x^2 + 3x - 1) can be derived using the relationship between logarithmic and exponential functions. The correct transformation leads to y = e^(x/3) + 1, indicating that the inverse function simplifies significantly. The discussion highlights the importance of recognizing patterns in cubic equations, particularly referencing Pascal's triangle for coefficients. A critical error was noted regarding the omission of a factor of three during the transformation process.

PREREQUISITES
  • Understanding of logarithmic and exponential functions
  • Familiarity with cubic functions and their properties
  • Knowledge of Pascal's triangle and binomial coefficients
  • Basic algebraic manipulation skills
NEXT STEPS
  • Study the derivation of cubic function inverses using algebraic methods
  • Explore the application of Pascal's triangle in polynomial expansions
  • Learn about the properties of logarithmic functions in depth
  • Investigate the graphical representation of cubic functions and their inverses
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Students studying algebra, mathematicians interested in function transformations, and educators teaching inverse functions in calculus.

tg43fly
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Homework Statement



Find the inverse of f(x)=ln(x^3-3x^2+3x-1)

Homework Equations



n/a

The Attempt at a Solution



y=ln(x^3-3x^2+3x-1)
x=ln(y^3-y^2+3y-1)
e^x=(y^3-y^2+3y-1)

i looked around for inverse of cubic functions and i found a monster of a formula:
http://www.math.vanderbilt.edu/~schectex/courses/cubic/
i really hope i missed something to find the inverse
 
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tg43fly said:
y=ln(x^3-3x^2+3x-1)
x=ln(y^3-y^2+3y-1)
e^x=(y^3-y^2+3y-1)
You dropped a very important factor of three in going from y=ln(x^3-3x^2+3x-1) to x=ln(y^3-y^2+3y-1).

i looked around for inverse of cubic functions and i found a monster of a formula:
http://www.math.vanderbilt.edu/~schectex/courses/cubic/
i really hope i missed something to find the inverse
Those factors of three should suggest something. Hint:Look at Pascal's triangle.
 
whoops
$$y=ln(x^3-3x^2+3x-1)$$
$$y=ln(x-1)^3$$
$$x=ln(y-1^3)^3$$
$$e^x=(y-1)^3$$
$$y=e^x/3+1$$
ty for the hint
 

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