In a exercise says:(adsbygoogle = window.adsbygoogle || []).push({});

Find max a min of [tex]f=-x^2+y^2[/tex] abaut the ellipse [tex]x^2+4y^2=4[/tex]

i tried [tex]-2x=\lambda 2x[/tex]

[tex] 2y=\lambda 8y [/tex]

[tex]x^2+4y^2-4=0[/tex]

then [tex]\lambda =-1[/tex] or [tex]\lambda =\frac{1}{4}[/tex] , but, ¿how i find [tex]x,y[/tex]????

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# Lagrange multiplier

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