St41n Messages 32 Reaction score 0 Thread starter Jun 17, 2013 #1 Can I do this: sup_(x,y) f(x,y) = sup_y sup_x f(x,y) ?
WannabeNewton Science Advisor Gold Member Messages 5,850 Reaction score 553 Jun 17, 2013 #2 Yes. Proof: http://math.stackexchange.com/questions/53794/simple-question-the-double-supremum