• biddy ( biddy@feddit.nl ) 
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    3 years ago

    In your example you lose distributivity. (2+4)2 is 22+4*2, which doesn’t matter for numbers but it matters for algebra. If addition comes first then there’s no way to represent distribution.

    • Kogasa ( kogasa@programming.dev ) 
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      3 years ago

      The distributive law, assuming commutativity and other axioms, is a*(b+c) = (a*b) + (a*c). Notice how it does not matter in which order you evaluate + and * in this expression due to my use of parentheses.

      PEMDAS is notation. It has no influence on the actual underlying math, only how we write it.