Confused on what to do

[vast marsh]

Doesnt the D, have to have two values?

[vernal obsidian]

okay good rectangle and good job computing of the critical point

it's important to remember you also have to check along the edges of your unit square.

because it COULD be the case that your critical point is a minima right

[vast marsh]

Is it saying the square is (0,0), (1,0), (1,1) and (0,1)m

[vernal obsidian]

yes

exactly right

so check along that square and those 4 lines

[vast marsh]

Like this?

[vast marsh]

.solved