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by Find second order partial and cross partial fxx = act dx 2 tyy : Jy 2 a f fxy = fy x = of ( fy ) ed Calculate : A. = (fx x) (fgy)-(fxy)2 Is there a relative minimum or relative maximum Is this positive or negative definite Given the following objective function f ( x .y ) = 4 x 2 - 9 xy + yz Subject to constraint *+y = 3 an Solve for y Note: I already did y = 3-x bJ Substitute eq'n 3 in eg'n O Note: (a- b]2 = a2 - 2ab +62 " Take derivative set= 0 [ solve for x* ] d) Take second derivative. Is it a relative MAXIMUM or MINIMUM $ Given function / Lagrange Multiplier problem] [ f ( x , y ) = 200 + 6 x 2 + 1042) 0 Subject to constraint |X +9 = 801 (2) ad Write the LAGRANGIANfunction 3 b) Find partial derivatives Zx - - - 2 and 2 7) 2 x