- #1
Cpt Qwark
- 45
- 1
Homework Statement
Find the minimum value of [tex]f(x,y)=e^{x+y}-2[/tex] within x≥0 and y≥0.
Homework Equations
[tex]D=f_{xx}(a,b)f_{yy}(a,b)-[f_{xy}(a,b)]^2[/tex]
Answer is -1
The Attempt at a Solution
So for all partial derivatives I got [tex]e^{x+y}[/tex] (and mixed), but when I calculate the discriminate (subbing in (0,0) I get [tex]D=e⋅e-(e)^2=0[/tex].
I was just confused on how the answer is -1 when the discriminate has to be larger then zero to be a minimum point.