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Glitch in the matrix (ani.social)

submitted 11 months ago by [email protected] to c/[email protected]

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[–] [email protected] 4 points 11 months ago (2 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.

[–] [email protected] 3 points 11 months ago (1 children)

I can say that this is a common thing in engineering. Pretty much everyone I know would treat 1/2x as 1/(2x).

Which does make it a pain when punched into calculators to remember the way we write it is not necessarily the right way to enter it. So when put into matlab or calculators or what have you the number of brackets can become ridiculous.

[–] [email protected] 3 points 11 months ago (1 children)

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

[–] SmartmanApps 0 points 7 months ago

1/2x and expect you to know which one I meant with no additional context or brackets

By the definition of Terms, ab=(axb), so you most certainly can write that (and Maths textbooks do write that).

[–] SmartmanApps 0 points 7 months ago

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.