This is going to be a weird question, but in textbooks when we're given the two spaces R^n and R^m, and they say something about R^(n+m), then are they referring to ordered pairs of ordered pairs? That is, if x is in R^n and y is in R^m, then R^(n+m) is the set of all ordered pairs (x,y). So for example if n = 1 and m = 2, then all ordered pairs of ordered pairs: (x, (y,z)) where x is in R and (y,z) is in R^2?(adsbygoogle = window.adsbygoogle || []).push({});

Or do they just mean an (n+m)tuple of real numbers?

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# Cartesian product of R^n and R^m

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