Exampleof second-degreeequationsrepresentinga simplemaximum.

ˆ y

=83.57-9.39x1+7.12x2-7.44x2
1
-87.69=- 9.02X2
1-2.13X2

-3.71x2

2

-5.80x
1x2

ˆ y

2

Exampleof second-degreeequationsrepresentinga simpleminimax.

ˆ y

=84.29

+11.06x1

+4.05x2

-6.46x1

2

-0.43x2

2

-9.38x1x2

ˆ y

-87.69

=

- 9.02X
1

2

-2.13X2

2

Exampleof second-degreeequationsrepresentinga stationaryridge.

ˆ y

=83.57

+10.23x1
=- 9.02X2
1

+5.59x2
+0.00X2
2

-6.95x1

2

-2.07x2

2

-7.59x1x2

ˆ y

-87.69