Thread: Help finding the extreme values

Hello,

I need to use the lagrange method to find the extreme values of


with this condition



I got this system of equations
(1)
(2)
(3)

And I tried to define y in terms of z, and insert in (3)
But I get the wrong answer after solving the new equation.

The right answer is
and

Would anyone mind to explain how to get to the right answer?

Thanks

Originally Posted by sebasto

I got this system of equations
(1)
(2)
(3)

And I tried to define y in terms of z, and insert in (3)
But I get the wrong answer after solving the new equation.

The right answer is
and

If you substitute in (3), you should get , so that , with solutions z = 4, –2. The given answer appears to list the coordinates in anti-alphabetical order, (z,y) rather than (y,z)!