The inverse of the exponential function

dalterego
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The inverse of the exponential function...

Homework Statement



Find the inverse of the function = e ^ (x^3)

Homework Equations



The inverse of the exponential function = the natural logarithm of that same function

The Attempt at a Solution



inverse of f(x) = ln(x^3) ?

This doesn't seem right.
 
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Nope. Let y=e^(x^3). Take Ln of both sides and express x in terms of y. Then replace y with x and you're done.
 


Alright, so is the answer

inverse of the function = (ln x)^1/3 ?
 


Yeah.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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