this post was submitted on 03 Apr 2024
1297 points (98.8% liked)

Science Memes

11161 readers
2814 users here now

Welcome to c/science_memes @ Mander.xyz!

A place for majestic STEMLORD peacocking, as well as memes about the realities of working in a lab.



Rules

  1. Don't throw mud. Behave like an intellectual and remember the human.
  2. Keep it rooted (on topic).
  3. No spam.
  4. Infographics welcome, get schooled.

This is a science community. We use the Dawkins definition of meme.



Research Committee

Other Mander Communities

Science and Research

Biology and Life Sciences

Physical Sciences

Humanities and Social Sciences

Practical and Applied Sciences

Memes

Miscellaneous

founded 2 years ago
MODERATORS
 
you are viewing a single comment's thread
view the rest of the comments
[–] [email protected] 7 points 7 months ago* (last edited 7 months ago) (3 children)

My calculator says -2² = -4, so yeah...

[–] ByGourou 7 points 7 months ago (2 children)

Isn't the "-" order of operations the same as a multiply ? I think I learned powers take priority over the "-" so your calculator would be right.
But either way if it can cause confusion you should use parentheses.

[–] [email protected] 3 points 7 months ago (2 children)

Every calculator I've used has separate negative and subtraction keys for this purpose. There is no order of operations to follow, it's just a squaring a number

[–] ByGourou 3 points 7 months ago* (last edited 7 months ago) (1 children)

I learned negative as being a separate operation where we need to apply the order of operations. I think it was something like : -2 is a diminutive for -1x2 so it uses the order of operations of a multiplication.
My calculator is the official one used in schools in France (ti-83 premium ce) and it says -2^2 = -4 with the negative key. I don't think it would make a mistake in such a simple concept.

But whatever these concepts can change depending on the field, country, level of education. What I mean is : it's unclear, so use parentheses. So (-2)^2 or -(2^2) are the correct ways to write it.

[–] [email protected] 2 points 7 months ago

I think it was something like : -2 is a diminutive for -1x2

Correct. Things that are usually left out of Maths expressions are plus signs, ones as multipliers/indices, and un-needed brackets. e.g. I could more fully write this as -1(4)², but that just simplifies to -4²

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

it’s just a squaring a number

The number being squared is 4, unless you put (-4)², otherwise it's 4² with a minus sign.

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

I think I learned powers take priority over the “-”

Yes, Exponents is the 2nd-highest precedence (after Brackets) - BEDMAS.

[–] [email protected] 3 points 7 months ago (1 children)

I would never write -n². Either ‐(n²) or (-n)². Order of operations shouldn't be some sort of gotcha to trick people into misinterpreting you, it's the intuitive reading of a well constructed mathematical expression.

[–] [email protected] -2 points 7 months ago

Either ‐(n²) or (-n)². Order of operations shouldn’t be some sort of gotcha to trick people into misinterpreting you

It isn't. With ‐(n²), n² is already a single term, so the brackets aren't needed.

[–] [email protected] 2 points 7 months ago

My calculator says -2² = -4

That's correct