• themeatbridge@lemmy.world
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    1 year ago

    Depends on whether you’re a computer or a mathematician.

    2(2+2) is equivalent to 2 x (2+2), but they are not equal. Using parenthesis implicitly groups the 2(2+2) as part of the paretheses function. A computer will convert 2(4) to 2 x 4 and evaluate the expression left to right, but this is not what it written. We learned in elementary school in the 90s that if you had a fancy calculator with parentheses, you could fool it because it didn’t know about implicit association. Your calculator doesn’t know the difference between 2 x (2+2) and 2(2+2), but mathematicians do.

    Of course, modern mathematicians work primarily in computers, where the legacy calculator functions have become standard and distinctions like this have become trivial.

    • A computer will convert 2(4) to 2 x 4

      Only if that’s what the programmer has programmed it to do, which is unfortunately most programmers. The correct conversion is 2(4)=(2x4).

      in the 90s that if you had a fancy calculator with parentheses, you could fool it because it didn’t know about implicit association. Your calculator doesn’t know the difference between 2 x (2+2) and 2(2+2), but mathematicians do

      Actually it’s only in the 90’s that some calculators started getting it wrong - prior to that they all gave correct answers.