• AHemlocksLie@lemmy.zip
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    2 months ago

    The P in PEMDAS just means resolve what’s inside the parentheses first. After that, it’s just simple multiplication with adjacent terms, and multiplication and division happen together left to right.

    6÷2(1+2)

    6÷2(3)

    3(3)

    9

    • mic_check_one_two@lemmy.dbzer0.com
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      2 months ago

      This is actually a generational thing. Millennials were taught “PEMDAS”:

      1. Parenthesis
      2. Exponent
      3. Multiplication
      4. Division
      5. Addition
      6. Subtraction

      But younger generations have been taught “BEDMAS” instead:

      1. Brackets
      2. Exponent
      3. Division
      4. Multiplication
      5. Addition
      6. Subtraction

      Notably, Division and Multiplication are swapped on PEMDAS and BEDMAS, to make this “both happen at the same time” more straightforward. But that only applies if the entire operation can happen at the same time.

      For instance, let’s say 6/2(3) compared to 6÷2(3). At first glance, they both appear to be the same operation. But in the former, the 6 dividend would be over the entire 2(3) divisor. Which means you would need to simplify the divisor (by resolving the multiplication of 2•3) before you divide. So the former would simplify to 6/6=1, while the latter would divide first and become 3(3)=9.

      Technically, if you wanted to be completely clear, you would write it using multiple parenthesis as needed. For instance, you would write it as either:
      (6÷2)(3)=9 or 6÷(2(3))=1 to avoid the ambiguity. Then it wouldn’t matter if you’re using PEMDAS or BEDMAS.

      • AHemlocksLie@lemmy.zip
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        2 months ago

        But in the former, the 6 dividend would be over the entire 2(3) divisor.

        I have never heard of or seen an example of anyone using / and ÷ in different ways. If you want multiple terms in your divisor, either write it as a large fraction with all relevant terms in the dividend or divisor, or use parentheses. This just seems like sloppy notation to me.