• gordon@lemmy.world
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    1 year ago

    So 1/2x is universally interpreted as 1/(2x), and not (1/2)x, which would be x/2.

    Sorry but both my phone calculator and TI-84 calculate 1/2X to be the same thing as X/2. It’s simply evaluating the equation left to right since multiplication and division have equal priorities.

    X = 5

    Y = 1/2X => (1/2) * X => X/2

    Y = 2.5

    If you want to see Y = 0.1 you must explicitly add parentheses around the 2X.

    Before this thread I have never heard of implicit operations having higher priority than explicit operations, which honestly sounds like 100% bogus anyway.

    You are saying that an implied operation has higher priority than one which I am defining as part of the equation with an operator? Bogus. I don’t buy it. Seriously when was this decided?

    I am no mathematics expert, but I have taken up to calc 2 and differential equations and never heard this “rule” before.

      • mcteazy@sh.itjust.works
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        1 year ago

        I’m an engineer. Writing by hand I would always use a fraction. If I had to write this in an email or something (quickly and informally) either the context would have to be there for someone to know which one I meant or I would use brackets. I certainly wouldn’t just wrote 1/2x and expect you to know which one I meant with no additional context or brackets

    • Sorry but both my phone calculator and TI-84 calculate 1/2X

      …and they’re both wrong, because they are disobeying the order of operations rules. Almost all e-calculators are wrong, whereas almost all physical calculators do it correctly (the notable exception being Texas Instruments).

      You are saying that an implied operation has higher priority than one which I am defining as part of the equation with an operator? Bogus. I don’t buy it. Seriously when was this decided?

      The rules of Terms and The Distributive Law, somewhere between 100-400 years ago, as per Maths textbooks of any age. Operators separate terms.

      I am no mathematics expert… never heard this “rule” before.

      I’m a High School Maths teacher/tutor, and have taught it many times.