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## #1 2015-10-18 07:42:15

katerinaaa
Member
Registered: 2010-01-27
Posts: 4

### How can I find the minima, maxima when I have multivariable problem

Hi, I would like your help in the following problem

Locate all relative maxima, relative minima and saddle points, if any, for the function
\$\$
f(x,y,z)=1-x^2-y^2-z^2
\$\$

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## #2 2015-10-18 08:23:02

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

### Re: How can I find the minima, maxima when I have multivariable problem

Hi;

Have you been taught Lagrangian multipliers?

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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## #3 2015-10-18 16:03:05

katerinaaa
Member
Registered: 2010-01-27
Posts: 4

### Re: How can I find the minima, maxima when I have multivariable problem

I know that I use Lagrange multipliers when I have constraints ..

Is there any example for my case to follow up .?

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## #4 2015-10-18 17:51:13

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

### Re: How can I find the minima, maxima when I have multivariable problem

Hi;

You can use 1 for the constraints. I am getting a maxima of 1 at (0,0,0).

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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