#help-36

1 messages · Page 233 of 1

candid pulsar
#

then this would be easier and more rigorous

vale vigil
#

I don't believe u are

candid pulsar
#

bro is not saitama

scarlet sinew
#

js stick to conventions bro angeryklein

candid pulsar
#

we are bound to have some sort of mental capacity

tranquil pine
#

Hi who need help

scarlet sinew
candid pulsar
#

and the majority of human population use.. this convention to make sense of the 3d plane

vale vigil
#

please do not engage more

scarlet sinew
#

you arent even

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??

vale vigil
#

wouldn't look good on your behalf

vale vigil
candid pulsar
vale vigil
#

bro

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have you even started college 1st year

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or are you still in school

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to speak about mathematics like this

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?

scarlet sinew
#

have you finished 9th grade lil bro

vale vigil
heady moon
candid pulsar
vale vigil
#

they literally have a choice to not talk when I'm the one asking for help and not them here

candid pulsar
#

look the answer to your question is

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yes, there are infinite possibilities

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just choose the one the lot goes with

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thats all

scarlet sinew
vale vigil
scarlet sinew
#

and now you’re doing ad hominem

vale vigil
#

<@&268886789983436800>

heady moon
#

crazy

scarlet sinew
candid pulsar
steep hatch
#

Why am I summoned

candid pulsar
#

as we have learned with evolution

turbid spear
#

What the hell happend here

quasi rapids
#

haiii :3

heady moon
quasi rapids
#

take a chill pill everyone

candid pulsar
#

just go with what your teacher suggested as convention

scarlet sinew
#

close plz

#

zzz

candid pulsar
#

its not my fault youre being adamant

steep hatch
vale vigil
# steep hatch Why am I summoned

look, I was going through my questions peacefully and back and forth and so; but these both people, suddenly started saying me "look we don't know that, only God can, what your purpose is...." WHO ARE THEY TO DEFINE MY PURPOSE LMAO

scarlet sinew
vale vigil
#

they have a literal choice not to help me if they don't know this subject

steep hatch
vale vigil
#

I don't even think they studied an actual course on the topics they're talking about

vale vigil
scarlet sinew
#

bro ragebaiting atp

steep hatch
#

@heady moon that's not helpful

heady moon
vale vigil
#

.

candid pulsar
#

he says its not rigorous enough to assume a coordinate system

heady moon
#

i drawback from now on

vale vigil
#

"you can take one of them " what is that supposed to mean? that just wrong on so many levels, we're talking in a maths environment here and not about what u feel

steep hatch
#

I think blurple is just using a common analogy that you're not understanding and hence are taking offence with

faint edge
vale vigil
#

or procedure

vale vigil
#

to the moderators here

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I didn't want this to be like this

faint edge
#

Blaming things on peoples feelings, telling them they can't participate if they don't meet whatever arbitrary educational qualifications etc

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That's not cool homie

candid pulsar
#

not all in math can be perfectly justified for

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we have learned with experience that this has sufficiently helped us

vale vigil
candid pulsar
#

as math develops, we will justify everything

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you can confirm with other fellow members if this is acceptable

vale vigil
faint edge
scarlet sinew
vale vigil
#

and u just didn't study it yet

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in your education

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and I don't think you answering it to me as the "TRUTH" instead of how you feel like makes the situation civil

faint edge
#

For higher dimensions lines you can define lines f(t)=tm+b for m and b two vectors and t a scalar.

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Fwiw

candid pulsar
faint edge
#

You don't need to pick a coord system. You are however kinda just hiding that a system of equations is around the corner

vale vigil
#

if not; this and this would be the same numerically

faint edge
#

In what sense?

vale vigil
#

here

scarlet sinew
vale vigil
#

These both would be the same numerically

faint edge
#

Once you want to explicitly write out equations of lines I suppose.

vale vigil
#

but to a third object, this changes real position and they're not the same

candid pulsar
#

yeah i think you just want to hide behind more and more complicated math in efforts of justifying your rigor

faint edge
#

I don't see why that's an issue though. You pick an origin even in the xy case.

candid pulsar
#

that is why i want you to pick a coordinate system

faint edge
#

y=mx+b measures x and y relative to the x and y axes.

candid pulsar
#

and work with it for now

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you are overthinking this

vale vigil
#

which direction would the x, y and z be towards

candid pulsar
#

in particular directions

vale vigil
#

if the question or the supplier literally doesn't give the direction

faint edge
candid pulsar
faint edge
#

So I don't see why it upsets you in higher dim

vale vigil
vale vigil
candid pulsar
#

convention.

faint edge
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We do it in 2-dim as well though.

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Why is 3-dim an issue?

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We even do this on the number line.

vale vigil
faint edge
#

You have the exact same problems in 2-dim

vale vigil
#

my brain doesn't visualise 2d as much as it does in 3d

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lemme show u some visual representations

candid pulsar
#

that is why you are asked to follow convention for now

scarlet sinew
#

seriously if you want to define axes as, say x points to the sun or y points to Saturn (if that’s what you mean by defining axis directions), it literally doesn’t change the line’s equation

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like

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at all

vale vigil
candid pulsar
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do you remember how x is to the right and y is to the top in a 2d plane in general for simplicity

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it could have been in any direction

vale vigil
# vale vigil

If u see here, the blue stuff is just the third object seeing

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and numerically, the left side point would be the same as the right side point (say 5,6,7 as the co ordinates with same basis vectors)

scarlet sinew
#

mathematics don’t give a shit about visual representation or about “directions”

faint edge
#

If this upsets you you should also be upset that you have to pick an origin, a distance between notches and a direction every time you visualize the number line.

vale vigil
vale vigil
#

point*

faint edge
#

Nobody disagrees that these things aren't rules

vale vigil
#

doesn't upset me

candid pulsar
#

sometimes it doesnt matter

vale vigil
candid pulsar
#

you dont need to rigor everything up

vale vigil
#

right?

faint edge
#

"Object" is kinda vague.

candid pulsar
#

survival is more important than trying to have a perfect visualization of 3 dimensional space

vale vigil
scarlet sinew
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why do you want to make directions matter

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?

vale vigil
#

alright how about this, I take u to a step of sequences with drawings

scarlet sinew
#

look even if i have a cube with three lines on top of it no matter how i spin it’s mathematically the same

faint edge
#

Part of why coordinate systems are useful is that we can rotate and stretch them in convenient ways to match various contexts and that we can transform back and forth between them.

vale vigil
candid pulsar
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look we get that they can be in any direction in space

faint edge
candid pulsar
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and yes spatially different

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but just

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fix ONE of those

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and work from there

vale vigil
#

now if y'all could, see my words for the next few minutes

vale vigil
# vale vigil

Over here, you have a 3 dimensional space, with basis vectors 1,0,0
0,1,0
And 0,0,1

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then you have a point as u can see, at 5,6,7

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right. now my idea is, we can get a different set up but with the same origin

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just like this:

candid pulsar
#

yes yes we can

vale vigil
#

the point is the same numerically

faint edge
#

Yes, you can rotate and scale without changing the origin for ex

vale vigil
#

now

candid pulsar
#

but fix one of those

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you are focused more on the "choosing" part, and less on the "working with the coordinate system" part

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the latter is what you need more

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fussing on this does no good

faint edge
#

The points exact coords depend on which set of axes you measure with respect to.

vale vigil
# vale vigil now

Alright now, theoretically, this change shouldn't affect anything at all... but here's a twist, it does

faint edge
#

But it does change things

vale vigil
candid pulsar
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and that moves with the system too

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?

vale vigil
#

and the points are different if u change things like this

faint edge
#

This diagram is nonsense to me.

candid pulsar
faint edge
#

Can you make it clearer what it means to you?

vale vigil
#

then u note down the observations of our third object

scarlet sinew
#

okay so basically the third object is fixed in space and not relative to the system

vale vigil
#

it would be situated at different points in space

scarlet sinew
#

is that what you mean

heady moon
vale vigil
#

And

vale vigil
vale vigil
faint edge
#

That didn't make things much clearer to me.

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What is the red line supposed to be?

scarlet sinew
scarlet sinew
#

?

candid pulsar
#

is THIS what you mean?

vale vigil
#

u dont have to take it too literally but like

faint edge
#

Kk what about the green crosses?

heady moon
#

ok basically what we are doing is we fixed blue object and rotated the axes?

vale vigil
faint edge
#

No worries

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Blue ones are also axes and green dots are pts in the green axes coord systems then?

candid pulsar
vale vigil
# faint edge No worries

and if u seem the other one after the right line to be kinda flipped: I did mean it to be different, but with the same origin

vale vigil
#

the blue is the third object seeing all this

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What I meant to show was:

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to the third object,

scarlet sinew
vale vigil
#

Seeing this

faint edge
#

So kinda like what blurple said?

vale vigil
#

would not be the same as seeing this

candid pulsar
scarlet sinew
#

okay we get it

faint edge
#

Christ calm down

vale vigil
#

perhaps

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but now

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do u not see a need to define the axes's direction

heady moon
#

can someone pin his 3 drawings

candid pulsar
#

and it made no sense

vale vigil
scarlet sinew
#

the orane thingy is ur “third object”

candid pulsar
#

i thought redrawing would make his point easier to see

faint edge
vale vigil
# scarlet sinew the orane thingy is ur “third object”

well not exactly, they're in the same space and to be in fair words with you, the flipping or changing isn't actual, I meant to show that u can interpret the same co ordinates in a lot of ways, and that's why I need it to have a direction

heady moon
faint edge
#

So, what I mean is we draw lines and pictures to visualize things, but those pictures may be different from the actual object.

scarlet sinew
#

that literally just

vale vigil
#

so do u mean to say

scarlet sinew
#

changes the observer’s position relative to the system

faint edge
#

If you have an equation of a line in the plane, you don't at all need to pick axes or anything like that.

faint edge
#

It already implicitly sorta carries that info regardless of how you draw it.

#

When you want to actually sit down and draw, then yah, sure you gotta pick some axes.

vale vigil
#

Do u mean to say these both points are in the same place

scarlet sinew
vale vigil
#

from which origin did the line generate?

faint edge
#

Well in the xy plane the origin is (0,0)

scarlet sinew
#

for xyz it’s (0,0,0)

faint edge
#

It's not a visual thing

vale vigil
# scarlet sinew relative to the system yes

I don't think you're seeing the point here, the idea what I'm saying doesn't actually flip the whole graph...

IF you realistically flip the whole graph, then u would actually have them to be at same points, but like my idea is to show that they CAN be intreperted like this, in a million different (infinite) ways

scarlet sinew
vale vigil
#

so we have to " Define a point that exists in 3 dimension at co ordinates 0,0,0"

faint edge
#

Basically nothing changes about what I said in the 3d case

vale vigil
scarlet sinew
#

tf

faint edge
#

Or in 2d by defining what you mean by R^2

faint edge
#

I want to point out something as well

vale vigil
#

because if u don't define that

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u can interpret it in a lot of ways

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like I showed u

candid pulsar
vale vigil
#

and u wouldn't know which line they're talking about

scarlet sinew
candid pulsar
#

and as for your contradiction

vale vigil
#

which

faint edge
#

Okay, but interpreting it for the sake of drawing pictures is irrelevant to the actual math

candid pulsar
#

yes, something might change between you and the points

faint edge
#

Beyond just intuition and drawing pretty pictures I mean

candid pulsar
#

but no one cares about your pov

#

only what is happening in THAT system is of interest

faint edge
vale vigil
faint edge
#

So you are right that for the purpose of visualizing, you do need more info such as camera orientation+position, screen dimension info etc

vale vigil
#

oh

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well

faint edge
#

Well sorta

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At some point we get a little philosophical about it I guess

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But the actual math we want to do is formal stuff in R^n

vale vigil
# faint edge Because representation =/= math

how did u get to the axiom of there can be a line between any 2 points then? without representation, can't u just say " The probability of the line going to the other point is 0 because there are infinite points in between "

faint edge
#

Why are we taking euclid as fact here?

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Euclid's geometry had many problems.

scarlet sinew
#

yo spot the difference mathematically real quick

vale vigil
#

well

vale vigil
faint edge
faint edge
vale vigil
#

I see

faint edge
#

You aren't wrong that there's some important stuff here as far as coord systems and translating between them.

candid pulsar
#

and its easiest to fix one of those easier-to-see POVs and work with your problem

faint edge
#

This is INCREDIBLY useful all throughout physics, cs and probably a billion other subjects.

vale vigil
#

all in all, this just tells me maths cannot show me a line to my eyes in any 3 dimensional world that has any sort of visual representation or detection of co ordinate systems

candid pulsar
#

but you can work with it in some way or the other

faint edge
#

That seems like the wrong takeaway imo

faint edge
#

The math itself, kinda sorta can and kinda sorta can't.

vale vigil
faint edge
#

Math has nothing to so with things irl besides us basing things off irl stuff.

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If you want your math to be tangible irl, at some pt you have to leave the realm of pure logical gymnastics

vale vigil
#

I could interpret this point to be in infinitely different positions

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depending on how

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I interpret the axis direction

faint edge
#

You wanna draw a line? Well you need writing tools, stuff to write on etc and you must cope with the fact that the object you draw may not be a perfect representation of the line you intended.

vale vigil
#

well sorry my net lagged

faint edge
vale vigil
#

but it seems troubling that

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even if we had an all powerful being that ignored all those imperfections of our physical world

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even in a mathematical 3d world

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u wouldn't be able to show it

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this just seems wrong on so many levels... do u see where I'm coming from

faint edge
#

Part of why cartesian coords are useful is because we can overlay them (imperfectly) onto many different real world scenarios to some extent.

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If we just had only one fixed global coord system everybody used, that would be incredibly inconvenient.

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The whole notion of coords is not to far off from us just laying a system of rulers on everything.

vale vigil
#

let's have a really simple case

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of 3 points

faint edge
#

Measurements are useful. Rulers are useful. If you glue a ruler to the ground so it can't move it becomes less useful.

vale vigil
#

one point's the observer, one point's the origin

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and another point is what we need to find

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the observer point gets the measurements as; origin at 0,0,0 basis vectors at so and so

faint edge
#

Yes relative coordinate systems are a thing.

vale vigil
#

and I would still be able to conclude the point is everywhere sort of

vale vigil
#

but how

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do u convey that the point is at one place

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with a relative co ordinate system

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can u teach me this relative co ordinate system idea

faint edge
#

You pick a coord system that you measure the position of the pt wrt

vale vigil
#

okay

faint edge
#

Think of it this way, you fix one set of axes, but you can simultaneously fix another set.

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You can measure positions of pts wrt either.

vale vigil
faint edge
#

This is actually also very useful in 3d graphics btw

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Pt in 3d space

vale vigil
faint edge
vale vigil
faint edge
#

So if you have two coord systems saying origin by itself is just vague.

vale vigil
#

I see

faint edge
#

A simpler example: you can have two rulers at once lol

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If I say "the 1 inch mark" which one do I mean?

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It is unclear.

vale vigil
#

if it's 2,4,5 here

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and 3,6,7 there

faint edge
#

They are relative to coord systems as well.

vale vigil
#

or

faint edge
#

When you write (1,2) in the xy plane for example you mean 1 unit along the x axis and 2 units along the y axis for ex (if you have multiple xy axes this is vague)

vale vigil
vale vigil
#

something that doesn't make sense to me is that

faint edge
vale vigil
#

then how do u define this co ordinate system to be an actual existing theory at all?

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if u can't prove it exists in one place

faint edge
#

Why do you think a coordinate system is a theory? What does theory even mean to you?

faint edge
vale vigil
# vale vigil if u can't prove it exists in one place

I mean sure, u do it via 3,2 = 3,2 but wouldn't something in 3 dimensional space ideas come and contradict this saying 3,2 can be interpreted in infinitely many ways even with just one origin and since it's 3d space, it did not be equal to every other point being the same, if so, 3d space wouldve collapsed into 0d one single point

faint edge
#

Well we can just represent points in the two coord systems differently.

vale vigil
#

if the user specifiied the direction

faint edge
#

There's no shortage of tuple notations.

vale vigil
#

Of which the axises are situated in

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via a line equation

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showing direction

candid pulsar
#

and you can work

vale vigil
candid pulsar
#

with convention

faint edge
#

Say I call (x,y,z) pts the points in coord system one and [x,y,z] pts the points in coord system 2

vale vigil
#

which 2 points would you pick for each

faint edge
#

I want to make it clear that this is a choice and we do not have to do it

vale vigil
faint edge
#

But typically in lin alg you learn about transformations and such

vale vigil
#

so which of these 2,3s would u pick for the other system to measure

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actually, a drawing would show this the best

faint edge
#

So you would provide a map that sends (x,y,z) pts to [x,y,z] pts and such

faint edge
vale vigil
vale vigil
#

Over to the left, u have co ordinate system #2

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it's deciding which point it wants to measure

faint edge
#

This is too vague

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Let me give you a different example

vale vigil
#

over to the right, the blue ball is just all the different possibilities of the axises that can be made with one origin

faint edge
#

Say you pick a coord system

vale vigil
#

that's why I put many points instead of one

vale vigil
faint edge
#

Say I go "nah ur coord system sucks, I want my own!" So I set my origin at (2,0,0) and then orient my axes the same way you did yours (just shifted).

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I can translate points in my coord system by just subtracting 2 from any x coord to get a pt in ur coord system.

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We can do similar things with rotations, I can even scale my coord system differently.

vale vigil
#

so

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essentially you're telling me that

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you would have one single point

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for both of those

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with a specific setting of the direction of their axises

vale vigil
#

even in spatially

faint edge
#

In this case I would have two different origins. One for each coord system and some orientation of the axes for each coord system.

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Lets also say I use the [x,y,z] notation for my pts and you use (x,y,z) notation for urs.

vale vigil
#

hold on

faint edge
#

My [0,0,0] is now your (2,0,0)

vale vigil
#

they're 2 different co ordinate systems

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and they share their own points in the first system

faint edge
#

Yes if you mean we can set up a bunch of different coord systems simultaneously

vale vigil
#

but if u bring them specifically

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u can get both of their co ordinates to match ONE point

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in visual space

vale vigil
#

but this seems like really impossibly hard

faint edge
vale vigil
#

have u discovered a method to do this easily?

vale vigil
faint edge
#

No explain it

faint edge
vale vigil
# vale vigil

and see that, if u place the cyan co ordinate system in a place where the white co ordinate system intertwines with it so that, both of them have a common point that in terms of co ordinates is the same

slate narwhal
#

maybe the only piece of intuition I can give you is that a 7cm object is 7cm regardless of whether you measure the thing from the 0cm mark (in which the object extends to 7cm) or the 5cm mark (in which the object extends to 12cm)
object's still 7cm either way.

likewise, suppose a point on Earth is at sea level, 0 deg lat, 0 deg long.
then I say, fuck the current lat/long/alt system, I'm defining my own!
0 degrees lat is now the south pole, and 0 degrees long is where I am.
does the point change locations? no! but I describe it a different way because I am using a different coordinate system.

coordinates are references, not absolutes!

vale vigil
faint edge
#

Stuff like rotating, translating and scaling coord systems is very easy to do via matrix multiplication. Your computer can do thousands of coord changes every minute.

vale vigil
#

let us say

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you have an arbitary direction for x, y, z

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in co ordinate system one

vale vigil
#

and now forget about this

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you have an arbitary direction for x, y, z for co ordinate system two

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and now say u pick any point 3,6

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now, if u situate these two co ordinate systems in. One single 3d space

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I mean... overlap them or something

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the chance of their point aligning, is well eh miscleaneous

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BUT

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there can be a point in the merged 3d Euclidean world

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where co ordinate system 1's 2,3

faint edge
#

Why are we worried about overlapping these points?

vale vigil
faint edge
#

You pick two coord systems and two arbitrary pts. They may not be the same pt. Why is this a problem?

vale vigil
#

without having to worry about the directions of the axises

vale vigil
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now that u say that

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how are u "measuring" this point?

faint edge
#

"Measuring" with respect to what?

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You have two coord systems.

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What are you measuring relative to?

vale vigil
faint edge
#

The same way you'd do in one coord system

vale vigil
faint edge
#

Just ignore the coord system you aren't using.

vale vigil
#

in one co ordinate system, I usually define 2,3 as a point that exists in a space like this;

faint edge
#

Nah

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Think about it, (2,3) in a particular coord system is RELATIVE to the axes.

vale vigil
#

and if it's real world and I have to locate the 2,3 I give up my hands because locating a 0d object is impossible in 3d world without mathematically saying it exists

faint edge
#

You don't define (2,3) after the fact.

faint edge
#

You pick a coord system and that tells you what (2,3) is

vale vigil
#

wait

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wait

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u don't need the co ord system first

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u already pick a point and ask " Which co ord system gives the answer of 2,3 for this"

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right?

faint edge
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I think that's kinda different.

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Say you have a sheet of paper

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You can draw a pt

vale vigil
#

is pt a point

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or what is it

faint edge
#

Then draw axes and ask what are the coords of my pt

vale vigil
#

is it a line

faint edge
#

Yeah pt=point my bad

vale vigil
#

hm

vale vigil
#

I can legit... draw INFINITe of those

faint edge
#

But before you draw the axes it doesn't make sense to ask what the coords of your point are. The coords are measurements relative to the axes

vale vigil
#

I mean.. pt can be, 3,6 9,8 10383,-0.000002

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whatever it wants to be

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how do u take one absolute thing

faint edge
vale vigil
#

what is your bias

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to pick one then

faint edge
#

Like why pick one?

candid pulsar
vale vigil
#

you're asking what the co ordinates of the point is

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so u have to pick one

candid pulsar
#

and you can discuss with others coherently

vale vigil
#

out of the infinitely many co ordinates

vale vigil
candid pulsar
#

that is called convention

vale vigil
#

other than not picking one

faint edge
#

A common thing that happens in physics

vale vigil
faint edge
#

Is that one coord system makes your calculations much easier to deal with than others

vale vigil
#

yeah

faint edge
#

You are right that you have many choices

vale vigil
#

pretty much

faint edge
#

But some choices are less practical in a given context than others

vale vigil
#

I wonder what that means for mister maths who doesn't care about visual representations or inconveniences

scarlet sinew
#

aint no way this convo still ongoing bro

faint edge
#

Say you wanna calculate something about the rotation of the earth for ex. Why set the origin so that the earth lies at (1000000000000000000000,0,0) as opposed to so that the origin lies at the center of the earth?

faint edge
cyan kayak
#

This is also not taking into account other schemes for specifying coordinates, like spherical, cylindrical, etc.

vale vigil
#

you can get a nice origin that takes up less ink in your paper

faint edge
#

We care about them insofar as they help as understand and solve problems.

vale vigil
#

I see

faint edge
#

Like the actual computations can become much simpler

vale vigil
#

yeah true

faint edge
#

You can often cook up a coord system with more convenient angles and distances for doing actual computations is what I mean.

vale vigil
#

hmm

#

alright

#

let's move on in the idea

#

you select a point pt

#

but what next.. if u can pick a nice co ordinate like 0,0

#

then?

odd violet
#

hi again

faint edge
#

Idk what ur asking?

vale vigil
#

but we've only gotten one

#

where's the second one

odd violet
#

Why is all of this going on again

faint edge
#

Sorry I'm still unclear. We pick a coord system and a pt, then we pick another coord system? Then what?

#

I'm assuming we've overlapped the two coord systems as well?

#

So, now we wanna measure the position of our pt in both coords?

candid pulsar
vale vigil
#

do u measure this point

faint edge
#

You do it the same way you do if you only had one coord system

vale vigil
#

From the other system, other than 0,0 system

faint edge
#

You just have two representations for the pt.

vale vigil
faint edge
#

You will get another representation for the point

vale vigil
#

you wouldn't define the same point of the origin/ this pt of co ord system 1

faint edge
#

If I call you by a different name do you become a different person? Lol

vale vigil
faint edge
#

We are in 2d?

vale vigil
#

is there not a mathematical formula that constricts the point's location to an exact

vale vigil
faint edge
#

Lets just do 2d since it is easier. The same reasoning will apply in 3d.

vale vigil
faint edge
#

Say you draw two sets of axes on the same sheet and a 3rd pt

vale vigil
#

or do u have a function

faint edge
#

Call the pt p

faint edge
#

Lets write coords in the fiest coord system as (x,y) and in the second as [x,y]

vale vigil
#

Hmm

#

okay

faint edge
#

If we want to know what x y make p=(x,y) we look at the axes of the first coord system and measure the distance along the x-axis and y-axis of the first coord system to get to our pt p.

#

If we want to know what x y make p=[x,y] we look at the axes of the second coord system and measure the distance along the x-axis and y-axis of the second coord system to get to our pt p.

#

We could even do this problem in 1d

valid carbon
#

oh wow

vale vigil
#

hmm did u define that both of these cord systems have the same basis vectors

faint edge
#

They don't

#

You should think of basis vectors as defining the axes of a coord system

#

In this case we have two diff sets of bases. One for each coord system.

vale vigil
#

like saying the point is 2,3 in regards to cord system a

faint edge
#

You have to be careful though

vale vigil
#

and 3,2 in regards to cord system b

#

would just be...

faint edge
#

We have two different ways to represent our basss vectors

#

*basis

vale vigil
#

2 units of a mountain and 3 units of an ant

faint edge
#

So for example (0,1) and [0,1] need not be the same

#

In fact our two bases will be {(0,1),(1,0)} and {[0,1],[1,0]}

candid pulsar
#

its more of "this way" and "this other way" rather than trying to match their "numeric values" up

faint edge
#

And these sets may genuinely be different

vale vigil
#

Ahhh i seeee

#

there was a different bracket

#

I thought it was the same

faint edge
#

Yes (1,0) means 1 unit along the x axis IN COORD SYSTEM 1

#

And [1,0] means 1 unit along the x axis IN COORD SYSTEM 2

vale vigil
#

I seeeeee

faint edge
#

(Sorry for caps spamming)

vale vigil
#

that's pretty funny lol

faint edge
#

The key point here is our coords are relative to whatever axes we measure them with respect to

#

It's a little silly but it's also kinda deep and important lol

vale vigil
#

I mean... these cord systems aren't related to each other right

#

like their axes are not dependent on each other

faint edge
#

So, I was trying to sorta get at that with the 3d graphics example

candid pulsar
#

and thats.. convention

vale vigil
#

so why the requirement of 2

candid pulsar
#

you only need the most commonly used one in many cases

vale vigil
#

right right because like

#

in camera and cinema shooting and stuff, u don't see the same picture of the care or something from every side

#

ohh this like a physics thing

faint edge
#

Say you wanna render a scene with a house and you wanna render a dog with birds spinning around its head. You have the global coord system, say you place the origin at the house

candid pulsar
#

better way to visualize it yeah

faint edge
#

For rendering the birds it would be a lot easier to draw them relative to the dog tho

#

So set a second coord system with the origin at the dog

vale vigil
#

perhaps in simulation maybe

faint edge
#

So long as you can translate this back into world coords (or whatever coords you are using) this is very useful

vale vigil
#

Yeah

#

it is

faint edge
#

But you see that these kinds of situations can get very convoluted and we can come up with many other examples of course

#

Choosing coords are exactly that, a choice.

vale vigil
#

hmm

#

a question over here

#

shouldn't this idea be created for something like computers

#

because in real life, we'd never be able to do anything 100% precisely

faint edge
#

This is used in computer graphics like I said lol

#

Well computers aren't 100% precise either ofc

vale vigil
faint edge
#

I tend to think of it as the real world being much messier than what we deal with in math.

#

This extends even to computers. Ieee floats aren't actually reals for example.

#

We use them as a way to represent reals

#

But that doesn't mean they are the same thing.

cyan kayak
#

As I mentioned casually yesterday, 100% of numbers are number that we have no way of representing in the real world. They require an infinite amount of information to specify. The numbers we deal with are a tiny tiny fraction of the more "interesting" numbers.

vale vigil
#

The most mathematical example to real worlds

#

might be computers

faint edge
#

Computation is its own bag of worms. Computers on a theoretical level can not do everything we can do in math. Computers irl can do less than what our models of computation can do.

vale vigil
#

then why are we focusing on a subject that's just not possible to do

#

I thought maths didn't focus about physical real world problems... so why categrozie this as maths and not physics

faint edge
#

Eh all of these subjects overlap in various ways

cyan kayak
#

and continuity

vale vigil
#

I see

faint edge
#

Math, computer science, engineering, physics, none of them exist in a vacuum. They interact.

cyan kayak
#

For instance, the following function is continuous if we consider only the rationals.

f(x) = x if x^2 > 2, x-1 otherwise

#

but "clearly" there is a discontinuity here

vale vigil
#

Why is colour not part of maths?

faint edge
#

You can model color

vale vigil
#

I mean...

#

it's entirely photons

#

and eyes

faint edge
#

I mean, if you think about it color is a real world thing.

#

So idk if you can do much better than modeling it.

vale vigil
#

but like

cyan kayak
#

There are very complicated models for colors that take into account human perception

faint edge
#

We have analogous situations for things like force

vale vigil
#

then wouldn't maths be talking about a non existent world

#

I don't get why real world and maths have to be seperate

faint edge
#

Idk dawg that's above my paygrade lmao

cyan kayak
#

There's nothing about math that says it has to model the real world.

vale vigil
#

after all, the real world is just one of the worlds that maths theoretically should be able to model

faint edge
#

I mean, they aren't separate in some ways and they are in others

cyan kayak
#

you can model imaginary worlds with math

vale vigil
#

hmm

faint edge
#

Math is sometimes called a "rational" science.

#

The idea is (roughly) that we're trying to work purely in logical terms

#

What happens irl is a separate concern.

vale vigil
faint edge
#

You are asking several different things here

#

For the logic question

#

The history of logic is full of people developing various logical systems and debating how effective they are

vale vigil
#

hmm

slate narwhal
#

the first two questions seem to have nothing to do with math and more to do with how humans categorize things and the nature of humans to explore more anyway

faint edge
#

I tend to take a view that I would consider kind of a logical pluralist pov.

#

There are many systems of logic one can use. They all have different pros and cons.

#

Math in particular tends to use a specific system of logic

valid carbon
#

We have three laws.

faint edge
#

Mostly because it works well for the types of questions mathematicians care about.

valid carbon
#

That's mostly it.

vale vigil
valid carbon
#

well axioms i guess

faint edge
#

If you read up on folks like cantor russel and godel you will find some interesting things along these lines

#

There are a lot of cases where things in logic weren't what ppl expected.

vale vigil
#

hmm

#

what makes u so confident that people aren't wrong now, just like how they were wrong before

faint edge
#

Well I wouldn't claim to be confident about much in general.

vale vigil
#

well

faint edge
#

I think with respect to logical systems you are guaranteed logical correctness only insofar as your logical system does what you think at does and only insofar as you used it correctly.

vale vigil
#

can u be truly 100% confident about it

faint edge
#

I doubt it.

vale vigil
faint edge
#

Well on one hand because it is interesting

#

On the other because it is useful

vale vigil
#

well yes

candid pulsar
#

hey its working out fine till now

#

why stop

valid carbon
#

'I do not know if there's possibly some way in which the 3 laws (which are very rudimentary) might break'

vale vigil
valid carbon
#

'Therefore logic is not worth studying'

faint edge
vale vigil
#

when countless generations have died

#

without knowing them

candid pulsar
#

🖋️ 🔥

faint edge
#

If not you might like reading about those things

vale vigil
#

I see

valid carbon
#

someone get this guy Camus /hj

vale vigil
#

Also, what are some of the other interesting topics like the ones we discussed a few minutes prior?

#

I just wanna get my head imagining an empty 3d space void

cyan kayak
#

I mean, you could argue that maybe math axiom that we use now are inconsistent and we'll eventually find a way to break all math, but until that point, we have a tool that has some interesting things that are useful and applicable to real life, and many other interesting things we can imagine. Worrying about maybe all math will break is rather useless, because it's working right now, and if it breaks later, we'll just amend the axioms to fix the issue.

vale vigil
#

and this stuff, like co ordinates, measuring things etc..

valid carbon
#

It's also not broken yet.

#

Unless you have counter examples to any of the 3 laws... ?

faint edge
#

For ex gerhard gentzen proved consistency of PA within zfc iirc

#

Hopefully I'm not butchering that

cyan kayak
#

my understanding of inconsistency problems, is that eventually you'll find a way to prove A and not A for some proposition A, which then breaks everything

faint edge
#

There are various strengthenings and weakenings of pa that people have been studying consistency of for a very long time

cyan kayak
#

and if our axiom set is one of those, then we just need to choose different axioms.

faint edge
#

You still are in a position where you have to answer "consistency of what" and "relative to what" for these kinds of qs.

vale vigil
#

well my idea was that.... you guys might have been missing something in broad daylight all this time, like a logic itself that you didn't apply to theories (a logic like if a exists, then a doesn't exists is false or something like that)

faint edge
#

There are multiple choices of foundations you could pick to discuss pa in.

vale vigil
#

when was the last logic that's significant discovered

faint edge
#

People study logic now

#

I study logic lmao

vale vigil
#

Oh lol

faint edge
#

Though I do computability in particular

#

So more pure logic stuff is not something i'm willing to claim to be competent in.

valid carbon
#

!occupied

final saddleBOT
#

Someone else is already using this help channel. If you need help with a question, please open your own help channel/thread (see #❓how-to-get-help for instructions).

vale vigil
# faint edge Though I do computability in particular

I have a question;
You would say a is not true if I believe something b as an axiom right,
But if I believe the opposite of b, then a would be true,
But if I believe an axiom that if something leads to something then it is false,
Then wouldn't a be false according to my axioms,
And if I believe another axiom that leads to a contradiction, how are u going to tell me that my ideas contradict so they're false?
Because I can believe that, if any ideas contradict, then they would be true

And if I take these axioms, I would have an absurd world, can u still compute this?

faint edge
#

"You would say a is not true if I believe something b as an axiom right"

Idk. Why would I say that? Lol

vale vigil
#

for example b says no dog exists

#

a is a red dog

#

a does not exist

#

something like this

#

but I change the rules of what I believe

#

then wouldn't my world still be a logical world

valid carbon
#

Why don't you, like, study basic logic?

faint edge
#

You can assume contradictions.

#

Nobody is stopping you.

cyan kayak
#

I think what he's pantomiming at is if you have some axiom set B, and this axiom set B implies not A, then if we have some other axiom set B' (which is somehow the "opposite" of B), then would that imply A.

#

And the answer to that question is there is no way to construct B', because 'opposite' doesn't have a meaning in this context.

faint edge
#

You're just stuck in a situation where (if you have "enough" logical oomf in your system), then you can just prove anything you like.

valid carbon
#

That wouldn't be terribly good of an axiom set would it

faint edge
#

Have you seen the proof that 0=1 implies russel is the pope?

vale vigil
vale vigil
#

but I think it's all related to the

#

axioms that you believe

cyan kayak
cyan kayak
#

we can adopt any set of rules we care to, just some make the game more fun than others.

faint edge
#

It's a pretty easy to read informal argument/story

vale vigil
#

so my question is

#

what would consider to come as an axiom in your book of logics

faint edge
cyan kayak
candid pulsar
#

how did we come to social studies lmfao

vale vigil
#

and logics should include the significant axioms most humans believe

faint edge
#

A lot of people like to think they are logical

#

But idk if ppl really are

slate narwhal
faint edge
#

I mean, I try to be logical but I would not say I am perfectly logical, consistent, etc.

vale vigil
#

if many people, believe many different axioms of the same idea

faint edge
#

Idk If I'd be willing to commit myself to laying out some criteria like that.

vale vigil
#

what's the criteria that decides which one you're taking

cyan kayak
faint edge
#

It doesn't do me much good in the immediate sense if I do. I could be wrong. My feelings may change.

faint edge
#

Sometimes you do wanna pick careful logical foundations for things.

vale vigil
#

there's only so much u can do about solving a cube

cyan kayak
vale vigil
cyan kayak
#

you're conflating a lot here

vale vigil
#

well it was an analogy, kinda bad but

faint edge
vale vigil
#

you gotta think out of the box sometimes

scarlet sinew
#

holy…

#

also hi guys how’s the convo going

faint edge
#

We can think about law of excluded middle without being like "law of excluded middle is something I 100% believe is true all the time"

vale vigil
#

true

vale vigil
scarlet sinew
#

getting a bit philosophical here are we

faint edge
#

I think ur lost in da sauce

vale vigil
#

What is your opinion on that?

#

actually

scarlet sinew
vale vigil
#

I'm lost here

faint edge
#

Idk seems like I don't have much of a reason to worry about that until it becomes an actual issue that affects me.

vale vigil
#

I don't think I should worry about it right now too

#

well

faint edge
#

It's fine to think about diff axioms and how they play with other logical notions.

#

I just don't personally see a point into committing myself to believing things I don't know are true.

vale vigil
# vale vigil I don't think I should worry about it right now too

it just came so in this conversation cause someone told me on a debate server a few days ago that, both a unicorn and laws of non contradiction don't have proofs, but u believe one more because it's true, and just like that god is something u beli- so and so..

valid carbon
#

well

scarlet sinew
#

urm

valid carbon
#

that escalated quickly

vale vigil
vale vigil
#

I wanna get to have more experience on mathematical concepts

faint edge
#

Most of the logical laws and ideas come from ppl observing things irl and trying to construct some kind of understanding of things.

vale vigil
#

just like co ordinate systems and I know one more that's called differential geometry

faint edge
#

This is a process that has happened for basically all of human history

lime nebula
#

oh my

faint edge
#

You construct a model, other people come and critique it. They construct their own models etc etc

vale vigil
#

I would think and have a major opinion on a child crying

lime nebula
#

Pre-uni measure theory back again?

scarlet sinew
vale vigil
faint edge
#

Idk if this is a debate so much as herec thinking about logic

vale vigil
#

but I don't know where to start

faint edge
#

I do think herec would prob get a lot out of studying more logic and math. Maybe some lin alg in particular.

cyan kayak
vale vigil
scarlet sinew
#

linalg is an okay path for him imo

vale vigil
#

but I guess I don't have a question right now

slate narwhal
#

!done

final saddleBOT
#

If you are done with this channel, please mark your problem as solved by typing .close

vale vigil
#

I can probably close this now

scarlet sinew
#

aight

#

it was fun

vale vigil
#

Yeah

valid carbon
#

Well

#

either it was

#

or it wasn't

cyan kayak
#

law of the excluded middle!

vale vigil
#

thanks for y'all

valid carbon
#

(im 100% confident come at me)

vale vigil
#

lol

scarlet sinew
vale vigil
lime nebula
final saddleBOT
#
Channel closed

Closed by @vale vigil

Use .reopen if this was a mistake.

candid pulsar
#

great run though

valid carbon
candid pulsar
#

ggs

final saddleBOT
#
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bold dust
#

A bag contains 4 red marbles and 2 blue marbles, and 2 marbles are drawn at random with replacement. The ratio of the probabilities that 0, 1 or 2 red marbles are drawn is a: b : c in simplest form, where a, b, and c are positive integers with no common factor large than 1. What is the value of 100a+10b+c

heady moon
bold dust
#

i dont know how to start

#

I think 2 choose 2 ways for 0 red marbles, 4 choose 1*2 choose 1 for 1 red marble, and 4 choose 2 ways for 2 red marbles

craggy plank
#

Looks good to me

#

But they’re looking for probabilities

#

You might need to modify the current information to proceed

leaden moon
#

consider each case

heady moon
#

so 4choose1 * 4choose1

bold dust
#

oh ok

tired walrus
#

then the first one's also wrong

#

also we may stop writing nC1 instead of n

heady moon
#

oh right

bold dust
#

wdym there's only 1 way for no red marbles to be chosen

tired walrus
#

2*2 ways for both blue, 2*4 for one of each, 4*4 for both red

tired walrus
#

you draw one, record its color, put it back, then draw one again

leaden moon
#

All of that over 8*7 ways of choosing

tired walrus
#

no, 8*8

heady moon
tired walrus
#

because. again. WITH replacement.

#

also i will again say writing nC1 instead of n is quite silly.

bold dust
#

where do you get 8*8 from?

leaden moon
bold dust
#

you mean 6*6?

#

there's only 6 marbles

heady moon
leaden moon
#

My brain got messed up sometimes

tired walrus
# heady moon 😢

what? are we gonna have to always pretend to write (number)C1 because "the number of ways to choose 1 object out of n" is somehow fundamentally different from "n itself"?

heady moon
#

writing C makes easier to understand as sometimes people get confused js numbers (has happened bfore)

leaden moon
#

$\left( \begin{array}[c] & n \ 1 \end{array} \right)$

soft zealotBOT
#

1 divided by 0 equals Infinity

$\left( \begin{array}[c] & n \\ 1 \end{array} \right)$
```Compilation error:```! LaTeX Error: Illegal character in array arg.

See the LaTeX manual or LaTeX Companion for explanation.
Type  H <return>  for immediate help.
 ...                                              
                                                  
l.49 $\left( \begin{array}[c] &
                                n \\ 1 \end{array} \right)$
You're in trouble here.  Try typing  <return>  to proceed.
If that doesn't work, type  X <return>  to quit.```
tired walrus
soft zealotBOT
tired walrus
#

much easier

leaden moon
#

Ty :)

bold dust
#

i have the possiblities but idk how to put it as abc

leaden moon
#

$\frac{\text{amount of ways that satisfies the condition}}{\text{amount of possiblities}}$

soft zealotBOT
#

1 divided by 0 equals Infinity

leaden moon
#

In ratio form: $a$, $b$, $c$ are just integers

soft zealotBOT
#

1 divided by 0 equals Infinity

leaden moon
#

So you might need to do some algebra

tired walrus
#

actually you dont

#

you know the denominator is the same for all three

#

why not simply clear it to begin with

bold dust
#

i got ratio 4,8,16 which simplifies to 1,2,4 but 2 and 4 share a common factor of 2 which is greater than 1

bold dust
#

but 2 and 4 share a common factor greater than 1

#

so idk what the question wants

leaden moon
bold dust
#

oh wait nvm im stupid

leaden moon
bold dust
#

.close thanks for helping

final saddleBOT
#
Channel closed

Closed by @bold dust

Use .reopen if this was a mistake.

#
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final saddleBOT
fathom meteor
#

<@&268886789983436800> scam bot

final saddleBOT
#
Channel closed

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fathom meteor
#

compromised account it seemed, unfortunate

final saddleBOT
#
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zenith violet
#

umm so like im trying to assign different defensive multipliers to pokemon based on their typing, so like =SUMPRODUCT(fighting column, steel column) gives me 15.5 so like do i do 15.5/18 = .861111 and then do HP * Defense / (.86111) (where higher values are better) or do i just do HP * Defense / (.5 * (19.5 + 15)) or HP * Defense / (.5 * (19.5 * 15))

im trying to understand which method would be mathematically correct. my bren hurt

https://pokemondb.net/type (using this chart)

desert mantle
#

well all of them calculate some number. but its unclear what you want that number to mean

#

I dont see where you pull the 19.5 and 15 from?

zenith violet
#

well eventually theyll be ranked but its just supposed to evaluate how defensive they are. 19.5 is the fighting column added together and 15 is the steel one

#

blank space means 1

#

essentially pokemon with better typings (like steel) should get a higher defensive rating than pokemon with bad typings (like ice) because of the damage multipliers to different types differ

desert mantle
#

well your 15, 15.5 and 19.5 already do that

#

lower number=better

zenith violet
#

ya but i also want to factor in it's HP and defense stats

desert mantle
#

you would also have to factor in spdef

zenith violet
#

well i have 2 columns: 1 called physical tanks and the other special tanks. physical will use defense and special will use sp def

wind vessel
#

I think it's also important how defence influence dmg taken

desert mantle
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I dont quite know how the damage formula works

wind vessel
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You could do for instance do "on average, what procentage of HP does 100dmg take?"

zenith violet
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uhhh lemme look it up

desert mantle
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say you attack the mon once with every type with a physical attack with base power 100 or so

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and then check with how much hp it survives

zenith violet
desert mantle
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from some standardized mon with/without stab. whatever

zenith violet
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im less concerned with how much hp a pokemon has left rather than how much % of it's hp is left

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so hp and defense can be weighted equally

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intuitively, higher hp and defense make it more defensive, and better typing multipliers make it better but idk how to make an accurate formula

desert mantle
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hp*def/15.5 would be fine

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its not like there is a "correct" answer here

zenith violet
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oke leme try it

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1 min

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yeh i think this works thx

#

.close

final saddleBOT
#
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final saddleBOT
#
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tranquil pine
#

HI hi

final saddleBOT
tranquil pine
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i have many hella other tries but all ended up w indeterminate forms

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i guess this one is the best one ever although im not really proud of it

obtuse hedge
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Where did the times 0 come from

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I got -infty and ended it there 🤔

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Oh I see it now

tranquil pine
tranquil pine
obtuse hedge
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I realized the way I did it was wrong 😂

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But taylor series may be a good workaround here

half raptor
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@tranquil pine Nice username

obtuse hedge
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\begin{align*}
\lim_{x \rightarrow \infty}x^3(e^\frac{1}{x+1} - e^{\frac{1}{x}}) 
&= \lim_{x \rightarrow \infty}x^3(\sum_{n=0}^\infty\frac{1}{n!(x+1)^n} - \sum_{n=0}^\infty \frac{1}{n!(x)^n}) \\
&= \lim_{x \rightarrow \infty}x^3(\sum_{n=0}^\infty\left(\frac{1}{n!(x+1)^n} - \frac{1}{n!(x)^n}\right)) \\
&= \lim_{x \rightarrow \infty}x^3(\sum_{n=0}^\infty\frac{x^n - (x+1)^n}{n!(x+1)^nx^n}) \\
&= \lim_{x \rightarrow \infty}x^3(0 + \frac{-1}{(x+1)x} + + \frac{x^2 - (x+1)^2}{2(x+1)^2x^2} + \dots)
\end{align*}
soft zealotBOT
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Coolempire93

obtuse hedge
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We can see that calculating any further terms will have > x^3 in the denominator, so any further terms will -> to 0

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And this limit is simple to resolve as $-x^3/x^2 \rightarrow -\infty$

soft zealotBOT
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Coolempire93

final saddleBOT
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@tranquil pine Has your question been resolved?

lyric obsidian
#

\qty......

final saddleBOT
#
Channel closed

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#
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Do not immediately ping people or roles. After 15 minutes, feel free to ping <@&286206848099549185> once.
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jagged flare
final saddleBOT
jagged flare
#

how does min(a,b)<sqrt(10)<max(a,b) imply that the leading digits follow the leading digits of sqrt(10)

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er wait

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nvm

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.solved