7.
a)
G(x, y) = 30·x + 15·y - (10·x + 5·y + 2·x^2 + y^2 + 2·x·y) = 20·x + 20·y - 2·x^2 - y^2 - 2·x·y
b)
G'(x, y) = [- 4·x - 2·y + 20, - 2·x - 2·y + 20]
c)
G''(x, y) = [-4, -2; -2, -2]
d)
-4·x - 2·y + 20 = 0
-2·x - 2·y + 20 = 0
Ich erhalte die Lösung: x = 0 ∧ y = 10