Find All the Local Maxima, Local Minima, and Saddle Points $$f ( x , y ) = 81 x ^ { 2 } + 72 x y + 64 y ^ { 2 }$$

question 352

Multiple Choice

Find all the local maxima, local minima, and saddle points of the function.
- $$f ( x , y ) = 81 x ^ { 2 } + 72 x y + 64 y ^ { 2 }$$

• A) f(9, 8) = 15,841, saddle point; f(8, 9) = 15,552, saddle point
• B) f(72, 72) = 746,496, local maximum; f(0, 0) = 0, local minimum
• C) f(0, 0) = 0, local minimum
• D) f(72, 72) = 746,496, local maximum

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Definitions:

Genital Stage

A phase in Freud's psychosexual development theory during which an individual's main source of pleasure is their genital area.

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A theoretical framework that asserts that human behavior and feelings are deeply influenced by unconscious motives and conflicts.

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