Partial Derivatives With N-Variables

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SUMMARY

The discussion centers on calculating the partial derivative of the function F(x_1,x_2,...,x_n) = nth-root(x_1*x_2*...*x_n) with respect to an arbitrary variable x_i. The proposed solution involves using the chain rule, yielding the expression (1/n)(x_1*x_2*...*x_n)^((1/n)-1)*(x_1*x_2*...*x_{i-1}*x_{i+1}*...*x_n). Additionally, the user aims to maximize F under the constraint G(x_1,x_2,...,x_n) = x_1 + x_2 + ... + x_n = c, confirming that the partial derivative G_x_i equals 1. The user seeks guidance on the correctness of their approach and the next steps in the optimization process.

PREREQUISITES
  • Understanding of partial derivatives and multivariable calculus
  • Familiarity with the chain rule in differentiation
  • Knowledge of optimization techniques in constrained systems
  • Concept of geometric mean in mathematics
NEXT STEPS
  • Study the method of Lagrange multipliers for constrained optimization
  • Learn about the geometric mean and its properties in multivariable contexts
  • Explore advanced differentiation techniques for functions of multiple variables
  • Review examples of maximizing functions subject to constraints in calculus
USEFUL FOR

Students and professionals in mathematics, particularly those studying calculus and optimization, as well as anyone interested in applying multivariable calculus to real-world problems.

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Homework Statement



Given F(x_1,x_2,...,x_i,...,x_n) = nth-root(x_1*x_2*...*x_i*...*x_n), how do I take the partial derivative with respect to x_i, where x_i is an arbitrary variable?

Homework Equations


The Attempt at a Solution



Would it just be:

(1/n)(x_1*x_2*...*x_i*...*x_n)^((1/n)-1)*(x_1*x_2*...*x_i-1*x_i+1*...*x_n)?
 
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You got it!
 
Alright, nice!

What I'd like to try to do with this problem is maximize F (the equation for the geometric mean) when it is constrained by G(x_1,x_2,...,x_n) = x_1 + x_2 + ... + x_n = c, where c is some constant. I can take the partial derivative of G with respect to x_i and get,

G_x_i = 1

But I don't really know if I am a) on the right track for this problem or b) how to proceed if I am on the right track. What should my next step be?
 

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