Critical Points of f(x,y)= x^{3} - 6xy + y^{3}

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SUMMARY

The discussion focuses on finding and classifying critical points for the function f(x,y) = x³ - 6xy + y³. The user initially attempts to solve for critical points but encounters discrepancies in their calculations. A correction is provided, indicating that the value in line 6 should be 1/4 instead of 1/8. Additionally, it is suggested to simplify the function by dividing everything by 3 for easier calculations, and Wolfram Alpha is recommended as a tool for verifying results.

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  • Understanding of multivariable calculus, specifically critical points.
  • Familiarity with the function f(x,y) = x³ - 6xy + y³.
  • Basic knowledge of using computational tools like Wolfram Alpha.
  • Ability to perform algebraic simplifications, such as dividing equations.
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  • Study the classification of critical points using the second derivative test.
  • Explore the use of Wolfram Alpha for verifying mathematical solutions.
  • Practice simplifying polynomial functions to facilitate easier calculations.
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Students studying multivariable calculus, educators teaching critical point analysis, and anyone interested in verifying mathematical solutions using computational tools.

jegues
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Homework Statement



Find and classify all critical points of,

f(x,y)= x^{3} - 6xy + y^{3}

Homework Equations





The Attempt at a Solution



See figure attached for my attempt at the solving all the critical points. I'm getting some weird numbers so I want to make sure I did this part correct before I start classifying them.

Does anyone see any problems?

Thanks again!
 

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hi jegues! :smile:

in line 6, your 1/8 should be 1/4 :redface:

(btw, it would be a lot easier if you divided everything by 3 first)
 
You can quickly check your work using wolfram alpha... and according to it, (0,0) is one but your other answers are wrong.
 

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