Question 634579
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Hi, Previously Posted
f(x, y) = x^2 + 2xy + 2y^2 -6y + 2
&#8706; f/&#8706; x = 2x + 2y
&#8706; f/&#8706; y = 4y + 2x - 6
 2x + 2y = 0
 2x + 4y = 6
    2y = 6
     y = 3   and x = -3
{{{f[xx]}}} = 2
{{{f[xy]}}} = 2
{{{f[yy]}}} = 4
D = {{{2*4 - 2^2 = 4 > 0}}} 
f(x,y) has minimum at (-3,3) 
f(-3, 3) = 9 -18 +18 -18 + 2 = - 7