What is the extreme f(x,y)=x^3+y^3-27xy ?

The extreme f(x,y)=x^3+y^3-27xy is Saddle(0,0),Minimum(9,9)

English

Español

Português

Français

Deutsch

Italiano

Русский

中文(简体)

한국어

日本語

Tiếng Việt

עברית

العربية

extreme f(x,y)=x^3+y^3-27xy

extreme points

f (x, y) = x^{3} + y^{3} - 27 x y

Saddle (0, 0), Minimum (9, 9)

Solution steps

Find the critical points:

(0, 0), (9, 9)

\frac{\partial ^{2} f}{\partial x ^{2}} = 6 y

D (x, y) = 36 x y - 729

Check the sign of at each critical point

Check critical point

(0, 0) :

Saddle

Check critical point

(9, 9) :

Minimum

Saddle (0, 0), Minimum (9, 9)

What is the extreme f(x,y)=x^3+y^3-27xy ?
The extreme f(x,y)=x^3+y^3-27xy is Saddle(0,0),Minimum(9,9)