Question

The function f ( x , y ) = x 3 + 27 x y 2...

The function

f ( x , y ) = x 3 + 27 x y 2 − 27 x

has partial derivatives given by
f x = 3 x 2 + 27 y 2 − 27,
f y = 54 x y,
f x x = 6 x,
f y y = 54 x,
f x y = 54 y, and
f y x = 54 y,

AND has  as a critical point. (You need NOT check this.)

Use the second derivative test to classify the point :

  

A.None of the other answers

B.Local maximum

   

C.Saddle point

   

D.Local minimum

Homework Answers

Answer #1

kindly please upvote this

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