Derivative Rule for y = f(X)^{g(X)}: Can Anyone Help?

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Discussion Overview

The discussion revolves around finding the derivative rule for the expression y = f(X)^{g(X)}, focusing on both partial derivatives and the application of exponential and logarithmic transformations. The scope includes mathematical reasoning and technical explanations related to derivatives.

Discussion Character

  • Technical explanation
  • Mathematical reasoning
  • Debate/contested

Main Points Raised

  • One participant seeks assistance in finding the derivative of y = f(X)^{g(X)}.
  • Another participant suggests using the transformation f(x)^{g(x)} = e^{f(x)g(x)} as a hint for differentiation.
  • A different participant proposes that the expression can be represented as e^{g(x) * ln(f(x))}, indicating a preference for this formulation.
  • There is a reference to Wolfram Alpha for the derivatives of f(x,y)^{g(x,y)} and a question about the notation f^{(1,0)}(x,y) and f^{(0,1)}(x,y), wondering if it denotes partial derivatives or specific points.
  • Another participant shares their intuition that the notation represents a bit vector indicating which variable the derivative is taken with respect to.

Areas of Agreement / Disagreement

Participants express differing views on the correct formulation for the derivative, and there is no consensus on the interpretation of the notation used in the equations.

Contextual Notes

The discussion includes unresolved questions about the notation for partial derivatives and the implications of the transformations suggested for differentiation.

verdverm
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I am having trouble finding the rule for the (partial) derivative of an expression like

y = f(X)^{g(X)}

can anyone help?
 
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Hint:

[tex]f(x)^{g(x)}=e^{f(x)g(x)}[/tex]
 
Make that eg(x) * ln(f(x)) and I'll agree.
 
Mark44 said:
Make that eg(x) * ln(f(x)) and I'll agree.

Oh my, I should pay better attention while posting :blushing:
 
hmm

I was just looking at:
wolfram alpha for
[tex] d/dx \ f(x,y)^{g(x,y)} = f^{(1,0)}(x,y)g(x,y)f(x,y)^{g(x,y)-1} + g^{(1,0)}(x,y)f(x,y)^{g(x,y)}log(f(x,y) \\<br /> d/dy \ f(x,y)^{g(x,y) } = f^{(0,1)}(x,y)g(x,y)f(x,y)^{g(x,y)-1} + g^{(0,1)}(x,y)f(x,y)^{g(x,y)}log(f(x,y) \\<br /> d/dx \ e^{f(x,y)g(x,y)} = f^{(1,0)}(x,y)g(x,y)e^{f(x,y)g(x,y)} + f(x,y)g^{(1,0)}(x,y)e^{f(x,y)g(x,y)} [/tex]

and was unsure what the [tex]d/dx \ f(x,y) \ is\ f^{(1,0)or(0,1)}(x,y)[/tex] meant in the previous equations.
Is it just the partial derivative? or partial at the point (1,0) or (0,1)?
 
my intuition is that it's a bit vector to show which variable the derivative is with respect to
 

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