• TWeaK@lemm.ee
      link
      fedilink
      English
      arrow-up
      1
      arrow-down
      1
      ·
      10 months ago

      PEMDAS is what they teach school children to help them learn. Like most such rules, it’s oversimplified and doesn’t quite work all the time.

      The proper way is to write a fraction top and bottom. Thus, 8(2+2) / 2 = 16, while 8 / 2(2+2) = 1. The implicit multiplication simply does not work if they’re split across the fraction.

      • [email protected]A
        link
        fedilink
        arrow-up
        2
        ·
        10 months ago

        PEMDAS sucks as a mnemonic, we can agree on this.

        Try 8/2(2+2) on an actual calculator that’s used by scientists.

        Something like a Ti-83 would show 16, not 1.

        • TWeaK@lemm.ee
          link
          fedilink
          English
          arrow-up
          1
          arrow-down
          2
          ·
          10 months ago

          Replace (2+2) with x:

          8 / 2x = 4 / x = 4 / (2+2) = 1

          Implicit multiplication takes priority over division.

          My Casio fx-991 gives 1. If I put in an explicit multiplication, then I get 16.