Among other things, one observes that the relative terms <math>\mathit{l}\!</math> and <math>\mathit{s}\!</math> do not commute, that is to say, <math>\mathit{l}\mathit{s}\!</math> is not equal to <math>\mathit{s}\mathit{l}.\!</math>
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Among other things, one observes that the relative terms <math>\mathit{l}\!</math> and <math>\mathit{s}\!</math> do not commute, that is, <math>\mathit{l}\mathit{s}\!</math> is not equal to <math>\mathit{s}\mathit{l}.\!</math>