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January 28th, 2013, 12:38 PM  #1 
Newbie Joined: Jan 2013 Posts: 3 Thanks: 0  Convex, concave or neither is convex/concave?
So I had this exam question about if this function was concave, convex or nor concave nor convex... e^(xy) My first guess I would use the maxima/minima theorem Like when A=f''xx = e^(xy) B=f''xy= e^(xy) C=f''yy= e^(xy) So AC  B = 0 ( (e^(xy)) * (e^(xy))  (e^(xy))^2)= 0 so nor convex nor concave right? 

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concave, convex, convex or concave 
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