Let $$A = \{ f\colon{\mathbb{R}^2} \to \mathbb{R}\} $$ be the set of all function with two varibles and let $$B = \{ f(x,y) = X(x)Y(y)\} $$ represent the set of all function with two variables that can be written as the product of two separate functions. The question is: is $B$ dense in $A$? Thanks.
2026-03-31 23:36:59.1775000219
Density in function space
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