The vast majority of the time, mathematicians use implicit multiplication (aka multiplication indicated by juxtaposition) at a higher priority than division. This makes sense when you consider something like 1/2x. It's an extremely common thing to want to write, and it would be a pain in the arse to have to write brackets there every single time. So 1/2x is universally interpreted as 1/(2x), and not (1/2)x, which would be x/2.

The same logic is what's used here when people arrive at an answer of 1.

If you were to survey a bunch of mathematicians—and I mean people doing academic research in maths, not primary school teachers—you would find the vast majority of them would get to 1. However, you would first have to give a way to do that survey such that they don't realise the reason they're being surveyed, because if they realise it's over a question like this they'll probably end up saying "it's deliberately ambiguous in an attempt to start arguments".

[–] Gordon@lemmy.world 5 points 1 year ago (4 children)

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.

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