Find the linear approximation of the function
Determine whether each of these functions is a bijection from R to R.
Find the local maximum and minimum values and saddle point(s) of the function. If you have three-dimensional graphing software, graph the function with a domain and viewpoint that reveal all the important aspects of the function. (Enter your answers as a comma-separated list. If an answer does not exist, enter DNE.)
f(x, y) = 3 − 2x + 4y − x2 − 4y2
|local maximum value(s)|
|local minimum value(s)|
|saddle point(s)||(x, y, f)|