Find All the Local Maxima, Local Minima, and Saddle Points $$f ( x , y ) = x ^ { 2 } + 7 x y + y ^ { 2 }$$

Multiple Choice

Find all the local maxima, local minima, and saddle points of the function.
- $$f ( x , y ) = x ^ { 2 } + 7 x y + y ^ { 2 }$$

A) f(7, 7) = 441, local maximim
B) f(7, 0) = 49, local minimum; f(0, 7) = 49, local minimum
C) f(0, 0) = 0, saddle point; f(7, 7) = 441, local maximim
D) f(0, 0) = 0, saddle point