(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Seems straightforward enough, Lagrangian optimization

2. Relevant equations

Find the max of x^-1 + y^-1 subject to the constraint m=x+y

3. The attempt at a solution

At first I thought no problems, x*=y*=m/2, however:

Using the Lagrangian formula yields derivatives as follows:

wrt x: -x^-2 - lambda

wrt y: -y^-2 - lambda

lambda: m-x-y

Putting the coefficients into a bordered Hessian seems to give a positive def. matrix implying a minimum? Is this a trick question or is it possible to maximize?

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# Homework Help: Lagrange again :facepalm:

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