this post was submitted on 03 Dec 2023
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[–] [email protected] 7 points 11 months ago (3 children)

Ah damn it. It took me ages to find a calculator app that fits my needs..... And now I find out it works like the one on the right.

[–] [email protected] 14 points 11 months ago (3 children)

... the one on the right is correct.... that's a jank ass calculator on the left that doesn't know how to do order of operations 8/2×(2+2) 8/2x4 4x4 16

[–] [email protected] 6 points 11 months ago* (last edited 11 months ago) (1 children)

There isn't a multiplication symbol though. By your logic something like 8÷2x would mean (8÷2)*x because order of operations

Or if you read 8÷2√x as (8÷2)*√x

Just notate 8÷2(2+2) as 8÷2x; x=(2+2) and you get it, you can substitute any complete expression with a variable in an equation and the logic stays the same.

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

You know sometimes both are correct.

[–] [email protected] 1 points 7 months ago

You know sometimes both are correct

Nope. That's what the order of operations rules take care of.

[–] [email protected] 1 points 7 months ago (1 children)

the one on the right is correct

No, it isn't.

8/2×(2+2)

...isn't the same thing as 8/2(2+2). You separated the term in the denominator, leading the (2+2) to get flipped into the numerator, hence wrong answer.

[–] [email protected] 1 points 7 months ago (1 children)

That would be 8/(2x(2+2)) if we were keeping it all in the denominator. Multiplication happens in the numerator if there are no parenthesis to distinguish it. If thr equation was written like this:

8


2x(2+2)

Then you would also be correct, but I have to respectfully disagree with your analysis.

[–] [email protected] 1 points 7 months ago* (last edited 7 months ago)

That would be 8/(2x(2+2)) if we were keeping it all in the denominator

(2x(2+2)) is the same thing as 2(2+2)

I have to respectfully disagree with your analysis

Which means you disagree with how Maths textbooks teach how to do this (see previous link).

[–] [email protected] 5 points 11 months ago (1 children)

Hiper Calc is the calculator app that I use. It's very good. When I ran this equation, it actually notified me how the operands should be grouped (weak or strong) and provided two answers. Honestly the whole issue can be avoided if you use more parentheses

[–] [email protected] 1 points 7 months ago

the whole issue can be avoided

...by following all the order of operations rules

[–] [email protected] 2 points 11 months ago

HP Prime, king of all. Or if you prefer open source NumWorks.