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

Find the maximum and minimum values of the function f(x,y,z,t)=x+y+z+t subject to the constraint x^2+y^2+z^2+t^2=400.

2. Relevant equations

I think the Lagrange multiplers can be used ∇f=λ∇g

3. The attempt at a solution

So I found ∇f=<1,1,1,1> and ∇g=<2x,2y,2z,2t>

and when i set each component equal to each other I get x=y=z=t. I don't know where to go from here, or if this was even the right path to take in the first place

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# Homework Help: Max and Min of a function of four variables

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