Solving Minimization Problem w/ Lagrange Multipliers

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SUMMARY

The discussion focuses on solving a minimization problem using Lagrange multipliers, specifically minimizing the function J(x, y) = x² + y² under the constraint C(x, y) = 4x² + 3y² = 12. The user attempted to derive the equations by setting up h(x, y) = x² + y² + λ(4x² + 3y² - 12) and found the derivatives dh/dx and dh/dy. However, the user encountered issues with the values of λ, concluding that the assumption of neither x nor y being zero may be incorrect and suggesting the possibility of multiple solutions, including both minimum and maximum values.

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Homework Statement



Solve the following problems using Lagrange multipliers
(a) Minimise J (x; y) = x^2 + y^2 subject to C (x; y) = 4x^2 + 3y^2 = 12:

Homework Equations


The Attempt at a Solution



i got h(x,y)=x^2+y^2+[tex]\lambda[/tex](4x^2+3y^2-12)

dh/dx=2x+8x[tex]\lambda[/tex]=0
dh/dy=2y+6y[tex]\lambda[/tex]=0

then i got [tex]\lambda[/tex]=-1/4=-1/3?impossible to slove it
 
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The values you obtained for [tex]\lambda[/tex] made an assumption that neither x or y are zero. Can you really make that claim? Also, maybe there is more than one solution (i.e. a min and a max)? Might help to draw a picture.
 
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