this post was submitted on 15 Oct 2024

-49 points (9.8% liked)

Ask Lemmy

26664 readers

1338 users here now

A Fediverse community for open-ended, thought provoking questions

Rules: (interactive)

1) Be nice and; have fun

Doxxing, trolling, sealioning, racism, and toxicity are not welcomed in AskLemmy. Remember what your mother said: if you can't say something nice, don't say anything at all. In addition, the site-wide Lemmy.world terms of service also apply here. Please familiarize yourself with them

2) All posts must end with a '?'

This is sort of like Jeopardy. Please phrase all post titles in the form of a proper question ending with ?

3) No spam

Please do not flood the community with nonsense. Actual suspected spammers will be banned on site. No astroturfing.

4) NSFW is okay, within reason

Just remember to tag posts with either a content warning or a [NSFW] tag. Overtly sexual posts are not allowed, please direct them to either !asklemmyafterdark@lemmy.world or !asklemmynsfw@lemmynsfw.com. NSFW comments should be restricted to posts tagged [NSFW].

5) This is not a support community.

It is not a place for 'how do I?', type questions. If you have any questions regarding the site itself or would like to report a community, please direct them to Lemmy.world Support or email info@lemmy.world. For other questions check our partnered communities list, or use the search function.

Reminder: The terms of service apply here too.

Partnered Communities:

Logo design credit goes to: tubbadu

founded 1 year ago

MODERATORS

Bluetreefrog@lemmy.world

candyman337@lemmy.world

TheSaneWriter@lemm.ee

TheSaneWriter@lemmy.thesanewriter.com

candyman337@sh.itjust.works

Asudox@lemmy.world

can@lemmy.ca

lemmy_bot@lemmy.world

beefbaby182@lemmy.world

AsudoxDev@programming.dev

-49

A book costs $1 plus half it's price. How much does it cost? (sh.itjust.works)

submitted 2 weeks ago by hal_5700X@sh.itjust.works to c/asklemmy@lemmy.world

21 comments fedilink hide all child comments

top 21 comments

sorted by: hot top controversial new old

[–] lvxferre@mander.xyz 26 points 2 weeks ago (1 children)

x = 1 + ½x → ½x = 1 → x = 2.

[+] b0thvar@lemmy.world -15 points 2 weeks ago (2 children)

Can't have the same letter for the function and the variable, should be like this: y = 0.5(x) + 1

[–] lvxferre@mander.xyz 13 points 2 weeks ago (1 children)

There is no function there, only an equation. And there is a single variable, "x", that represents the price of the book.

"x = 1 + ½x" is the same as "the price of the book is $1, plus half of the price of the book".

[–] b0thvar@lemmy.world -3 points 2 weeks ago (1 children)

Ok, call it an equation or a function, it doesn't matter what it is called, the point was that the original comment is only true for the value that was used.

In the original comment we have "x = 1 + ½x" and the example used was with a cost of two (x=2) to show that the equation was true (ending in 2=2).

However if 4 is used instead (x=4) then we have ( 4 = 1 + ½[4] ) which results in an inequality (4=3) which is false.

Which is why I initially commented with a different letter on either side of the equal sign.

If you prefer to only put the value of x on the right side on the equal sign and not the left side, then a common notation for that is f(x) = 1 + ½x, which is also referred to as function notation.

https://en.m.wikipedia.org/wiki/Function_(mathematics)

[–] lvxferre@mander.xyz 2 points 2 weeks ago (2 children)

Ok, call it an equation or a function, it doesn’t matter what it is called

What it is called does matter because a function obligatorily maps one set of values into another set of values, and that is not what I was doing because IDGAF about a full set dammit, but a single value that symbolises a price where OP's statement is true.

However if 4 is used instead (x=4) then we have ( 4 = 1 + ½[4] ) which results in an inequality (4=3) which is false.

As even 11yos know, but apparently not you, you don't solve an equation (or a set of equations) by arbitrarily assigning values to the variable.

If you prefer to only put the value of x on the right side on the equal sign and not the left side, then a common notation for that is f(x) = 1 + ½x, which is also referred to as function notation.

Congrats for not getting a value but a slope. 👍 /s

Juuuuuuuuuuuuust in case that your confusion is related to my usage of "→": it's clear by context that the symbol is being used for "implies".

[–] sntx@lemm.ee 3 points 2 weeks ago (1 children)

This discussion is incredibly funny, because it is a discussion.
I personally prefer the equivalence (⇔) over the implication (⇒) since I like to emphasize that the statement is true in both directions. Well and having an incorrect base leads to funny statements on implications: x = x/2 ⇒ x = π is true.

[–] lvxferre@mander.xyz 0 points 2 weeks ago

I'm glad that at least someone is getting some value out of it.

The equivalence symbol would be even better, indeed. But I can't type it with just AltGr+I, so I went for the simple arrow.

[–] b0thvar@lemmy.world 0 points 2 weeks ago (1 children)

So after rereading the original post (which could have been written clearer) I think your equation in your original comment is written in a way that doesn't reflect the original post.

According to the original post the right side of the equal sign is cost plus half of the cost where cost is defined as $1. So then the equation would be x = 1+ ½(1) which solves to x = 1.5.

As even 11yos know, but apparently not you, you don't solve an equation (or a set of equations) by arbitrarily assigning values to the variable.

You are correct that assigning arbitrary values is not how to solve an equation (at least by hand), but I wasn't trying to solve the equation, I was showing that the equation as written would not be true unless 2 was used.

Juuuuuuuuuuuuust in case that your confusion is related to my usage of "→": it's clear by context that the symbol is being used for "implies".

Since the "→" notation is an alternative notation for a function, it made reading the math in your posts and the words in your posts contradictory. It would seem that you didn't read the Wikipedia link since the "→" notation is described there.

[–] lvxferre@mander.xyz -1 points 2 weeks ago* (last edited 2 weeks ago)

So after rereading the original post (which could have been written clearer)

Okay... I'll stop reading here.

The original post is clear as day, even with the spelling mistake.

There's a certain level of lack of basic reasoning that I'm still willing to play along with; but this comment is past that. Not bothering further with you.

[–] hddsx@lemmy.ca 6 points 2 weeks ago

It’s N equation and not a function…

[–] user224@lemmy.sdf.org 13 points 2 weeks ago

It costs nothing because you get it from LibGen.

[–] Vanth@reddthat.com 11 points 2 weeks ago (3 children)

The same question was posted yesterday. Are you a bot fishing for engagement?

[–] xmunk@sh.itjust.works 16 points 2 weeks ago

It's actually chatGPT and it just figured out outsourcing the questions to lemmy is more computationally efficient than burning through a few dozen video cards to derive the answer.

[–] hal_5700X@sh.itjust.works 5 points 2 weeks ago

Yes, Dave.

[–] supertonik@sopuli.xyz 1 points 2 weeks ago

This question was popular on Reddit few days ago.

[–] Kolanaki@yiffit.net 7 points 2 weeks ago

$1.50

[–] jjagaimo@lemmy.ca 6 points 2 weeks ago

$3.50

[–] rickyrigatoni@lemm.ee 2 points 2 weeks ago

Two bananas and a pineapple.

[–] JackbyDev@programming.dev 1 points 2 weeks ago

https://www.wolframalpha.com/input?i=x+%3D+1+%2B+0.5x

[–] biggerbogboy@sh.itjust.works 1 points 2 weeks ago

About tree fiddy

[–] rob_t_firefly@lemmy.world 1 points 2 weeks ago

"Its price," not "it's."