Question 1200274
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*[tex \Large k] is the *[tex \Large x]-coordinate of the vertex of the parabola.


Substitute *[tex \Large y] for *[tex \Large f(x)].  Then solve for *[tex \Large x] in terms of *[tex \Large y].  Then swap *[tex \Large x] for *[tex \Large y] and replace *[tex \Large y] with *[tex \Large f^{-1}(x)] on the domain established by the first part of the problem.

																
John
*[tex \LARGE e^{i\pi}\ +\ 1\ =\ 0]
My calculator said it, I believe it, that settles it
*[illustration darwinfish.jpg]

From <https://www.algebra.com/cgi-bin/upload-illustration.mpl> 
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*[tex \LARGE \ \ \ \ \ \ \ \ \ \  
								
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