#help-36

1 messages · Page 232 of 1

vale vigil
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to the correct original pov of what the exam paper meant by 1,1,1

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you have to correct where ur axis is placed in terms of direction

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to get the right 1,1,1

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now u can argue, that in a world with no other object, not even points

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this can be useless

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but in a world (3d btw) with any other object (if we forget there are infinite points already and objects aren't necessarily required)

vale vigil
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even with the same 0,0,0 or origin

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now y'all can talk

candid pulsar
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ok so you have two problems essentially

vale vigil
vale vigil
onyx peak
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Well, if we have a fixed coordinate system, then we can describe the location of each point exactly. Of course if you twist the axes or swap them, change them or sth like that, you change the whole system, which was ought to be fixed.

If we wanna communicate position of certain points, we have to agree beforehand on one common coordinate system, with oriented and labelled axes which we will both use.

A good example of this (although not a cartesian system) is the earth and the latitude-longitude coordinates. If I tell you some coordinates, you'll know exactly where on earth they are. Because we agreed on the coordinate system beforehand

TL;DR, you have to fix a coordinate system and not change it, then the coordinates will work

vale vigil
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if at all

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you have a intuition of how 3 dimensional spaces work, and how linear "twisting" works

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you'd understand why I didn't "change" anything

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when I changed the direction of axises

vale vigil
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I do not have a vengeful intention behind changing this

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and I completely agree with u that we need to have a defined co ordinate system

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you'll later understand that's what I'm tryna argue for

vale vigil
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the literal intention behind me showing you that I changed it is

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the fact that you.... say it with me... CAN

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change it

candid pulsar
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but.. i) you are unsure how to define the coordinate axes such that the point the examiner calls to be at (1, 1, 1) matches with what YOU have defined

vale vigil
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over here, all u gave was which point was 0,0,0 and u gave me basis vectors

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and then u gave me a point to locate, 1,1,1

clear moon
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you yourself admitted that changing the axes doesn't actually change anything. so as long as people agree to your axis directions it doesn't matter what the "true" axes are, assuming you're looking for some sort of universal basis

vale vigil
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god forbid this mis understanding

candid pulsar
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that is, you argue that there are infinite possible ways to define the basis vectors, and therefore you are not sure how the grid would actually look like

vale vigil
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god forbid this mis understanding again

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alright

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we're back to two minutes of no talking pls

clear moon
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it's unnecessarily restrictive to want to look for some true established coordinate system, the freedom to change coordinates are useful in all sorts of math

vale vigil
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I was trying to show you, that;
If you give me a point and call it 0,0,0 as the origin, and if u give me basis vectors 1,0,0 - 0,1,0 and 0,0,1 for example.

vale vigil
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then I am ABLE to show 2 different representations

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like the ones I showed in the picture

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{ SAME basis vectors, SAME origin, JUST twisted the directions of x, y axises WITHOUT any hinderance in the question }

candid pulsar
clear moon
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it follows from the definition of a basis for a space that any point in that space is uniquely representable in that basis

candid pulsar
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which is essentially just changing the basis vectors

vale vigil
candid pulsar
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the axes are a representation of the basis vectors

vale vigil
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one more minute of silence please

candid pulsar
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changing them means you are changing the basis vectors

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sure

clear moon
vale vigil
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pls one more minute of silence

bold turtle
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Just let him cook

vale vigil
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what I'm trying to show right now

bold turtle
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-# Let the kitchen burn

vale vigil
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what I'm trying to show right now is

vale vigil
vale vigil
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please calibrate over this

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for a good 2 minutes of ur life

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I did not change anything

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I ended up with an answer

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with the same conditions y'all set

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and I ended up with a different, perfectly right answer

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that's what I'm tryna show

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it's self contradictory therefore you need an absolute direction for x, y and z axis in terms of a line equation of where they are

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to actually locate a point

vale vigil
onyx peak
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Okay, if we talk concretely, I fixed origin (0, 0, 0) at London's ground. My basis vector (1, 0, 0) goes to Birmingham and (0, 1, 0) goes to Norwich, (0, 0, 1) goes to say 10km above london. I think, that means that (1, 1, 1) will surely be 10km above Lincoln, is that wrong? If so, could you tell me where your second answer would end up being?

clear moon
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if you let e1 = (1,0,0), e2 = (0,1,0), and e3 = (0,0,1), you can write (2,0,0) as 2 * e1 + 0 * e2 + 0 * e3. what's the second representation? in other words, how else would you write (2,0,0) as a * e1 + b * e2 + c * e3?

vale vigil
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but in 3 dimensional space

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you did not define me a direction

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for this x axis, y axis and z axis

vale vigil
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the destination may not, given the process you are given with

bold turtle
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The destination's BIRMINGHAM ffs

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It does not matter the coordinate system involved; the destination is clear

vale vigil
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the destination wouldn't be Birmingham

bold turtle
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The maths does not contradict itself here, because you're using a different description

vale vigil
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it would be the ocean

bold turtle
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Okay so

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When we switch basis vectors, there is a way to convert from one basis to another

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This is the fundamental property of linear algebra

vale vigil
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I can't be more clear to you

bold turtle
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Yes, and I'm being as clear to you in kind

vale vigil
hasty mist
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how civilised and learned

vale vigil
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I'm not converting the basis vectors to different one

candid pulsar
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ah

vale vigil
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do u understand this?

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or do u not

candid pulsar
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so if you change the basis vectors

bold turtle
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Er... but you are LITERALLY DESCRIBING THIS without knowing it

vale vigil
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I do not change the basis vectors

candid pulsar
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the destination noted by (1, 1, 1) changes

bold turtle
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Yes, yes

vale vigil
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oh.. my God

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okay

candid pulsar
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thats literally what you are saying

vale vigil
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shall we have

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5 minutes of silence

bold turtle
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If you're changing where x, y, z are pointing on the outset, I hate to break it to you, but that is literally the fuxking definition of a change in basis_

vale vigil
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for my dead brain cells

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to gain back life

valid carbon
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alright we're all leaving

vale vigil
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please

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let me explain you with pictures

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just don't talk please

clear moon
vale vigil
vale vigil
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it is called 0,0,0 the origin of a co ordinate system which in near future, u will construct

vale vigil
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that u are given, respectedly for x y and z axis

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Alright

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This is what you are given

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ALL of u be clear, these are very important for u to understand me

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Next;

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I'm going to start the process

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of finding 6,7,8

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@clear moon @valid carbon @bold turtle @candid pulsar

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we found the point

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taking any direction of x, y, z we did not care

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okay?

vale vigil
valid carbon
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i just wanna point out

vale vigil
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DON'T SAY ANYTHING

valid carbon
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good 'yay' drawing

vale vigil
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do you AGREE WITH THIS

bold turtle
vale vigil
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oh

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u don't agree that we found the point?

bold turtle
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No, I don't agree that we didn't care about x,y,z

vale vigil
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sorry

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my mistake

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we did care for the x, y, z

valid carbon
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wdym you cant just agree with him

vale vigil
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but not in terms of hereC's serpant's direction

bold turtle
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Right, so this is going to change your argument, don't you see that?

vale vigil
bold turtle
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Sure

vale vigil
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and hereC's serpant also agrees with this

bold turtle
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why are you speaking in the 3rd person

vale vigil
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We didn't take a point that's like 10 kilometeres far away nf say it's 6,7,8

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we actually measured everything and like.. took the correct 6,7,8

vale vigil
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without messing up

bold turtle
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Also, you know coordinates are written with brackets, right?

vale vigil
vale vigil
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it alings up with 6 units of x

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or basis vectors for more convenience of mathematical ocd

bold turtle
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7 of y, and 8 of z, yes

vale vigil
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yep

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do u agree?

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that is perfect

bold turtle
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Now, you zip it for 5 minutes

vale vigil
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NOW we're back to silence of 5 more minutes

vale vigil
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u stop here this is the most crucial part

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pls

bold turtle
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So you shouldn't have pinged us BEFORE you were finished.

vale vigil
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u agree that we found a point with a conditions PLS STOP TYPING NOW

vale vigil
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if u agreed

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u do, now lemme show u some other thing

bold turtle
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Look, a few people had agreed to give you 5 minutes to explain yourself; so don't try and ping us before your argument is done. Lay out your ENTIRE argument, without pausing for whether someone has to AGREE with you, because otherwise you're just getting frustrated whenever someone explains to you why that is a hurdle.

Please, by all means, continue - but DO NOT PING ANYONE UNTIL AFTER YOUR "THESIS" IS DONE.

vale vigil
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what if

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we took the point like this?

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both of THESE answers are valid

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we didn't change the first answer to get this

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I REPEAT

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I REPEAT

hasty mist
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Truly one of the drawings in the history of all drawings

vale vigil
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WE DID NOT

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WE did not change the first answer to get this

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We got this answer of our own

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We did not twist the first answer to get this

valid carbon
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this is getting to spam levels of heading font

vale vigil
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we just took any arbitary directions of x, y, z axis for our own sake, that just... was different than the first answer's

clear moon
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why are we big now

valid carbon
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yeah no stop that

vale vigil
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Please dont care about that rn

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the more important thing is see what I'm saying

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" I did not twist the first answer "

valid carbon
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i can read normal sized fonts

vale vigil
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" Even though this looks twisted, this is a completely valid answer that we got on our own"

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" You would have agreed to this, if I sent this instead of the first answer"

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" This being different doesn't make 2 points by the way, it just says we could have gotten any right answer "

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" Please don't confuse this with thinking I changed and twisted it myself, I did not have an answer for this second version already that I twisted... I literally made it based on the question "

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" And therefore the part where I finish off is saying that.... in 2 dimension, this would have been the same if it actually aligned up with 6,7 of 2d plane"

vale vigil
vale vigil
# vale vigil

" Ending off, if u did not get anything cleared, re read all of this from here, if still not... go ahead and type"

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@bold turtle @valid carbon @candid pulsar @onyx peak
You don't need to reply to my ping rn, just read everything and if u still did not get anything, please reply then. it will be better for us

bold turtle
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-# SO STOP PINGING US, I TOLD YOU THIS.

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-# IF YOUR ARGUMENT IS NOT FINISHED...

candid pulsar
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can you go through this entire thing in 2D just for the record

vale vigil
# bold turtle -# IF YOUR ARGUMENT IS NOT FINISHED...

I do not want to flood the chat to explain to your autisti- sorry for the different use of English, that I finished the argument and if u read it properly bi- sorry for the misuse of English language, you would understand that u pinged u after I finished my argument

vale vigil
bold turtle
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Okay, this is far enough.

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<@&268886789983436800>

vale vigil
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I don't think it really does in 2d as well

valid carbon
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okay waes

vale vigil
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all I want is

valid carbon
vale vigil
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before a punishment

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and let someone learned, to reply everything

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I believe strongly that

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someone will understand

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without a mis understanding

valid carbon
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hi hayley

barren hound
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I think we've reached the point of establishing that this server is not going to be able to help you diagnose and remedy your core confusion, unfortunately

vale vigil
# valid carbon hi hayley

you are laughing in a child's face when he's asking a question for knowledge and you are harrassing him and then complaining that he got angered because of you, all u can do is just walk away and say " Don't involve me in this "

vale vigil
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what I said

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I'm actual and in good faith

bold turtle
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THEN DON'T JUST INSULT PEOPLE.

hasty mist
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Even someone as learned as I must concede that I am unable to assist with your confusion. It truly lies beyond the reach of my considerable intellectual apprehension.

vale vigil
valid carbon
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i did plenty of good faith discussion yesterday

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HOURS OF IT

vale vigil
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This is the major part

valid carbon
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oo hi ann too

vale vigil
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and u forgive me and we forget about this

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I will not do such thing

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anymore

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I just was tired

valid carbon
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uh huh

heady moon
vale vigil
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yes I will not, I'm here to just gain knowledge please don't mis understand me

heady moon
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its been 3 days

valid carbon
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maybe youll be given a break

vale vigil
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no but we are on the best straw of the talk right now

clear moon
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i'm unironically convinced that talking to chatgpt would help you way more than anyone in this server could lol

vale vigil
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I can't leave it at this when I've spent hours of countless explaining to u what my question is

tired walrus
vale vigil
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and when these few minutes of

heady moon
valid carbon
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blud thinks calling people autistic in the math server is an insult

vale vigil
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no but like... it would take someone 5 minutes

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to end this argument right now

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that's the stage it is in

candid pulsar
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uh huh

heady moon
clear moon
barren hound
# vale vigil I do not want to flood the chat to explain to your autisti- sorry for the differ...

While people have been very eager in helping you with this (and some have been what I would call overeager), I don't think the medium of discord chat will be an appropriate venue for this. I would encourage you to find someone that you can talk with in real time, with the aid of a physical piece of paper or whiteboard and possibly a beer if age appropriate.

I will also insist that you not use autistic as an insult, and that you not call us bitches; if you continue to do things like that we will need to take more drastic action.

old quarry
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guys why dont all of u become this active when i open a help channel 😭😭

clear moon
robust mulch
vale vigil
barren hound
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no, this is not an appropriate way to talk to a student here

vale vigil
barren hound
vale vigil
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alright

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I give u my word

bold turtle
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Let's start with this part for now.

valid carbon
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something like that.

bold turtle
vale vigil
# bold turtle Let's start with this part for now.

thank you, I want to claim that it is different than changing the basis. we are not changing a basis at all, we are in fact, getting a new different answer but that's a different basis than the one we could have taken as an answer

bold turtle
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Sorry, you've lost me at the first hurdle then

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You've got a second answer that's in a different basis, you're saying?

vale vigil
vale vigil
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yes.

bold turtle
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Okay, so, here's the thing.

vale vigil
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and the major point being, these answers were not dependent on each other

vale vigil
bold turtle
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If your answer is in a different basis, congratulations, you have changed the basis.

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This is what changing the basis is, by definition.

vale vigil
bold turtle
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Correct; we've had to establish one.

vale vigil
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hold on for one sec

vale vigil
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I'm telling you that... we can get a different answer itself

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we don't need answer

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from the point of the question

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we define a basis of our own in each answer because the question doesn't give one

bold turtle
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Weirdly, and you're gonna have to bear with me here, I'm actually going to pull up a map from the HITMAN series, because I think it's going to be the best way to explain this to you, unironically

vale vigil
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not by changing the basis of an answer, but by creating one ourselves

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and the basis is obviously gonna be different to most of the other answers (this isn't something mathematical but like...)

bold turtle
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Here is the Berlin map from HITMAN III.

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If I use the terms "map-up", "map-down", "map-left" and "map-right" to describe moving up, down, left and right (respectively) along the map as shown, would you agree that the DJ Booth is to the map-left of Agent 47 here?

vale vigil
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Yes

bold turtle
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But is it West of 47?

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(be very careful here; there's something in the first image that would help you)

vale vigil
bold turtle
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You sure?

vale vigil
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I'm sure

bold turtle
valid carbon
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okay thats a very hidden compass

bold turtle
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I'll grant you that, yh

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But it is there nonetheless

vale vigil
bold turtle
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You can be a bit more specific

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Supposing that North was facing map-downright?

vale vigil
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south east?

bold turtle
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yee

vale vigil
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okay

bold turtle
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But, do you see how "South East" does not match "map-left" in name only?

vale vigil
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I do

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we have infinite directions not just 4

bold turtle
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We've had to use the context that this map has been devised in the first place to deduce any comparison

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Whenever you have a question in coordinate geometry, the map is the question

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A well-written question provides you such a map to begin with, by default

vale vigil
bold turtle
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Since when did I deduce this map?

valid carbon
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...noooo

bold turtle
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I've been GIVEN this map to start

valid carbon
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do you know what deduction is

vale vigil
valid carbon
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imma plug more another roof here

bold turtle
#

Yeah, and the game has given me this map

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I didn't theorise it

vale vigil
valid carbon
# valid carbon do you know what deduction is

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The word "deduction" is...

▶ Play video
vale vigil
#

I don't see what you're asking me here

vale vigil
bold turtle
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You're working under the false assumption that a question does not give you basis vectors to define a coordinate geometrical space

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They definitely do

vale vigil
bold turtle
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When a question gives you coordinates, for example, such a basis is inherently implied

bold turtle
vale vigil
vale vigil
vale vigil
bold turtle
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Suppose if I gave you some coordinates, say the origin (0,0) of a 2D map (two dimensions are simpler for you to get this concept properly)

vale vigil
# vale vigil Basis vectors;

We did take the basis vectors as it is for both of our answers, we just took different relative directions of those basis vectors

bold turtle
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This inherently already implies there is an x-direction and a y-direction, and that they are non-parallel, so that they cover the space

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This is already what we mean by "giving coordinates"

heady moon
vale vigil
bold turtle
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Having a dimension by DEFINITION does capture a relative direction

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Else, it is NOT a dimension

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You MUST understand this before anything else in this discussion.

vale vigil
bold turtle
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This is why they're described with vectors, by the way

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And not scalars

vale vigil
bold turtle
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And what I'm trying to explain back to you is, when you define a dimension, it already HAS a direction implied

vale vigil
vale vigil
# vale vigil

@bold turtle if u see here, there's 3 coloured lines that are basis vectors

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let's say they have an arbitary direction, without the loss of generality

bold turtle
# vale vigil

Is this in 3D? even despite me saying that working in 2D would make this easier for you to get?

vale vigil
vale vigil
# vale vigil

these are 3 more basis vectors, that.. quite infact.. are just as linearly spaced as the first 3 ones, and also, we have the same point of origin here

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but if u try to form a point

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or a vector

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they'll end up in different positions

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that's why I argue direction matters, the axis's direction should matter, in 3d space

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I'm just waiting for you to ask me a question like "you just flipped it, you obviously changed it "

bold turtle
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you just flipped it, you obviously changed it
is not a question, for starters;
but if I DID respond with this, your point seems to be that you disagree that this is true?

vale vigil
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but nope, here's my actual response

vale vigil
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( the initial question was about the origin's location of which point it is, and the basis vectors, and the amount of linear spacing, like how the graph is)

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based on this I took this answer

bold turtle
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But look, the initial question inherently gives you a basis the literal moment they tell you any coordinates

vale vigil
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a basis x, y, z

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but not which direction it points to

bold turtle
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Right

vale vigil
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so this answer is completely valid

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is it not?

bold turtle
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Look

vale vigil
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why does this seem flipped to u when the first answer didn't

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what would have happened if I showed u this as the first answer

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these are literally derived from the same question

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I can't be more clear to advocate for a need of direction of the axises to be relative instead of x, y, x direction

bold turtle
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When we say a coordinate (2,5,6), we're inherently saying that relative to an origin and some notion of a unit, we have a point "2 units in the x-direction, 5 units in the y-direction, and 6 units in the z-direction from the origin"

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Do we care where specifically the literal x-, y-, and z-axes are?

bold turtle
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not really

vale vigil
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that's just confusion

vale vigil
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you fail to understand, that, THIS is also an original answer

bold turtle
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It.. actually isn't

vale vigil
bold turtle
vale vigil
# vale vigil

there's nothing saying that, axises situated this way is the original answer

bold turtle
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Firstly, the plural of axis is axes

vale vigil
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we derived this answer from question yes

vale vigil
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but we derived this also from the same question

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yeah, just different direction of axes

bold turtle
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"Derived" how?

vale vigil
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the question didn't specift the direction of axes

vale vigil
vale vigil
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you tell me in mathematical language how we derived this

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I'll copy paste it for the other answer

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it would be the same; valid and correct

bold turtle
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No, the onus is on YOU to tell me how; it's YOU who said we "derived" these in the first place

vale vigil
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we never had an answer to depend upon for the direction of the axis

bold turtle
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You're working under the assumption that our mouths are yours

vale vigil
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that said everything, including the basis vectors and point of origin

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and said to find a point x, y, z okay like 5,6,7

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from it, can we derive a valid answer as this?

bold turtle
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Then your answer, (5,6,7), whatever it may be, already uses the same basis

vale vigil
bold turtle
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It now reads "5 units in the x-direction, 6 units in the y-direction, and 7 units in the z-direction from the origin"

vale vigil
# vale vigil

in here just imagine a point a bit right side to the white line (I can draw it if u want)

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can we get a valid answer like this

bold turtle
vale vigil
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I do, not.

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I do not

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that's valid

bold turtle
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So then we're all good; the maths hasn't broken down, do you not see that?

vale vigil
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I didn't say the system was flawed

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I said the system didn't apply to that

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and if u continue with me on 3 dimensional space you'd see where I'm arguing from

vale vigil
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as of this point in our discussion

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maths hasn't broken down

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cool?

#

now if you hold on with me , can I ask you this question

bold turtle
# bold turtle So then we're all good; the maths hasn't broken down, do you not see that?

If you decide on changing where x-, y- and z- point in the first place, do you not agree that (2,5,6) and (5,6,7) still refer to relative points, that both still mean:
"2 units in the x-direction, 5 units in the y-direction, and 6 units in the z-direction from the origin"
and
"5 units in the x-direction, 6 units in the y-direction, and 7 units in the z-direction from the origin"
?

vale vigil
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please bear with me to know why

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Alright

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So, there's a point we need to find. 5 units in the x, 6 in the y, 7 in the z

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I've constructed a graph to plot this out

vale vigil
# vale vigil

@bold turtle this point reads 5 units in x direction, 6 units in y direction and 7 units in z direction

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so, is this correct of the question "find 5,6,7 with all the units"?

bold turtle
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Where each direction corresponds to which basis vector colour there?

vale vigil
bold turtle
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That's not a yes no question

bold turtle
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I'm asking you which colour is which of xyz

vale vigil
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Yes

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I mean.. they correspond very well to 5,6,7 co ordinates

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take yellow as y, red as x and white as z direction

bold turtle
vale vigil
vale vigil
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and asked us to plot out the point 5,6,7

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we can just ignore the fact that most of the points are not plottable with a finite data

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also we ignore our error fact

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and assume the point we plotted is 5,6,7

bold turtle
#

Look, knowing whether it's a good question or not takes years, if not decades, of experience, and it's not really that easy to explain why, suffice it to say that it's a poor question.

vale vigil
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its a euclidean 3d space

vale vigil
#

going back here (if u couldn't point the flaw in the question

spring haven
valid carbon
#

well more like intuition

vale vigil
# vale vigil

is this correct? we Derived a point 5,6,7 true to it's co ordinates

#

Then is it a correct representation and have we correctly located the point

#

that we were asked to

#

have we?

bold turtle
valid carbon
#

it's not a good question because it doesn't mean anything-

valid carbon
#

You might as well say 'find (5,6,7) with all the chicken sandwiches'

vale vigil
#

it means to show u something and for you to stop it by saying it's a bad question makes it inable to serve it's purpose

#

u dont just say it's not a good question without understanding it's purpose

#

right now if I tell u "there's a need to define a relative direction for axes"

#

you just would say "what, this person is nonseical"

#

and when I try to give the intuition, by taking u to the necessary question first

bold turtle
vale vigil
#

you say "what, this is nonsensical I'm not going further"

valid carbon
#

points dont have units

vale vigil
#

5,6,7 is a point

#

accept it or not

#

it's a 0 dimensional point

#

u can't put 3d objects in it

valid carbon
#

points are 0 dimensional.

#

they also dont have units

spring haven
#

what do you mean when you say 5,6,7? that statement itself requires a basis to make any sense

vale vigil
valid carbon
#

can you find (5,6,7) with all the chicken sandwiches

vale vigil
#

with basis vectors

#

1,0,0
0,1,0
0,0,1

#

and with a origin 0,0,0

spring haven
#

okay sure

vale vigil
#

we know the origin's location

spring haven
#

and what point are you making

vale vigil
#

now we're needing to locate 5,6,7

#

all I'm asking is

vale vigil
#

is this a correct representation

#

of locating it

#

the point perfectly aligns with 5,6,7's position

valid carbon
#

Sure then I guess.

bold turtle
#

It is a representation of describing a coordinate-triple, yes

vale vigil
#

so have we located the point at 5,6,7

#

alright cool

#

cool now bear with me

valid carbon
#

you can make pictures

vale vigil
#

bear with me, I'm not finished yet

spring haven
#

drawing a 3D thing in 2 dimensions is gonna cause some confusions anyway, I'll take your word for it

vale vigil
vale vigil
valid carbon
#

ill do you one better

vale vigil
#

this also matches with 5,6,7 perfectly

#

so is this a correct representation of 5,6,7?

valid carbon
spring haven
#

if you change your basis vectors to point in the opposite direction

vale vigil
spring haven
#

fundamentally it's a different point, it's like you flipped your whole space

vale vigil
#

no hold on here

#

u dont talk that high level stuff yet

valid carbon
# vale vigil we just changed the directions of x, y and z axis so that it would

How do you translate back and forth between coordinate systems that use different basis vectors?
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vale vigil
#

is it a valid point 5,6,7 now?

valid carbon
spring haven
#

in a different basis, yes

vale vigil
#

now here tell me

valid carbon
#

If you talk about change of basis (even without knowing it), you'll get a reply about... change of basis.

spring haven
#

any point can be made to have coordinates 5,6,7 in an appropriate basis

vale vigil
#

Alright I think it's time to stop your words, I have a really, beautiful thought experiment (it's literally this but like a story please don't think I create something else nonsensical here, unless u do after reading it)

spring haven
#

time to stop your words is crazy

#

i'm using that next time

bold turtle
#

@vale vigil
I'm telling you this right now:
you need a lot of experience, and that includes possibly hundreds of worked examples, on 2D coordinate geometry.

You might think this irrelevant, and maybe people your age might think so too. However, the vast, VAST majority of the concepts you're trying to grapple with in 3D exist in 2D and they can be explained in 2D as well. To this end, however, you need to put in the effort to go through these examples AND answer questions on these topics, and a lot of them.

This is not me gatekeeping you - it is your own lack of experience and underlying knowledge that is limiting your grasp on this. I can appreciate that this is tricky as a concept, but that's because you need much more solid foundations like this. To use an analogy, you're trying to fly a rocket to the Moon here, yet your rocket doesn't even have wings.

valid carbon
#

(i dont think rockets have wings waes)

bold turtle
#

Not the point.

valid carbon
#

(sure but the more you know)

-# fins i think

bold turtle
#

I personally will not entertain this discussion any further than I have done, which I think was far more than I would have liked myself to have done.

valid carbon
#

Yeaaah same, possibly

#

hopefully

#

I'm just going to reiterate some resources that are good:

#
  1. Another Roof.
#
  1. 3Blue1Brown
#
  1. ...KhanAcademy
#

You have homework.

#

At this point you're mostly just wasting people's time. It is now on you to do some due diligence on your part and read through the resources people have given you.

vale vigil
# vale vigil Alright I think it's time to stop your words, I have a really, beautiful thought...

So, there exists a 3 dimensional euclidean space, with a lot of objects, perhaps more than 2 3 dimensional objects for your sake of understanding.
Now, we have 2 humans trying to communicate via different rooms (different rooms just meaning; they can't see each other, and just read words or talk words, they can't show anything) .
What they're trying to communicate is really silly: person 1 , whom we call Billy, is operating a space ship that has no windows to see, actually let's assume we have just 2 3 dimensional objects somewhere floating in space, cool with that?

Now, Billy is trying to fly his spaceship to person 1 , whom we'll call silly.
Silly can see everything as Billy is coming towards him, silly can use co ordinates and mathematics to explain Billy everything.

The task is really simple, silly sees an object, that if billy's spaceship hits, Billy dies.
That's why silly has to say the co ordinates of that object, with respect to billy, we ignore a lot things, like 3 dimensional objects not being points, and time;
let's suppose that Billy and like his spaceship, is one point at 0,0,0 and we are given basis vectors as well, and the object is a point as well, now all silly has to do; is convey billy the point's exact location so that billy understands the exact point where it is, and doesn't die

vale vigil
vale vigil
vale vigil
hushed sequoia
spring haven
#

you've introduced a lot of layers of complexity here

hushed sequoia
#

Should people want to answer, they'll do it on their own

spring haven
#

such as the fact that the spaceship is moving

vale vigil
#

ignore everything like that, it's a thought experiment but u get the idea

#

points, co ordinates, correct direction of basis vectors

spring haven
vale vigil
#

what does basis even mean

#

is basis "basis vectors"

spring haven
#

and that's the problem, you fundamentally don't understand what you're talking about

vale vigil
#

is basis "the number of dimensions x, y, z.... n"

spring haven
vale vigil
vale vigil
#

so would u consider

#

1,0,0
0,1,0
0,0,1

#

a basis?

spring haven
#

yes that's a basis

vale vigil
#

this basis, is it 1,0,0
0,1,0
And 0,0,1?

#

suppose we wanted to keep the basis vectors as those

#

is it a basis

#

I mean is it a valid basis sorry not if they are the basis

vale vigil
#

if I wanted to keep vectors as

#

1,0,0
0,1,0
And 0,0,1

spring haven
#

there's a distinction you need to make between vectors and coordinates. The problem is that, in R^3 (which is 3D euclidean space) they look pretty much identical

vale vigil
spring haven
#

Vectors do not change with whatever particular basis you choose. They are simply points

Coordinates are how you describe a vector with respect to a particular basis

vale vigil
vale vigil
#

a particle axis

spring haven
#

a particular basis

vale vigil
#

right my bad

#

and the basis vectors, with respect to a particular axis

#

right?

spring haven
#

the problem in R^3 is that you can't really describe a vector without coordinates

#

unlike other vector spaces

#

which I suspect is part of where your confusion is coming from

vale vigil
#

are u saying that

spring haven
vale vigil
#

is impossible in R^3?

#

are u saying this?

spring haven
#

no?

vale vigil
#

so are u saying that

#

this with the basis vectors being that, is possible in R^3?

#

just say yes or no if u want to, no need to clear my confusion on some other topic which I may not have a confusion of

vale vigil
#

this particular thing specifically

spring haven
#

I don't understand your question

vale vigil
#

it's a yes/no question

vale vigil
#

with the vectors being

#

1,0,0
0,1,0
0,0,1

#

for 3 dimensional euclidean space

vale vigil
spring haven
#

yeah sure

#

what would those vectors be then

#

in your basis

#

like (-1,0,0) (0,-1,0) and what looks to be some other random vector

vale vigil
#

-1, 0,0 is a co ordinate where our vector is scaled by -1 * basis vector of x (we ignore 2 zeros of x here)

vale vigil
#

for both of the other basis vectors

#

dot products probably

#

but it's NOT what we care about right now

vale vigil
# vale vigil

All we care is, if this is possible with basis vectors being 1,0,0
0,1,0
0,0,1

#

then

#

is THIS possible with basis vectors being 1,0,0 0,1,0 and 0,0,1

spring haven
vale vigil
#

same 3d euclidean space

spring haven
#

you've just drawn some vectors on some axes

vale vigil
vale vigil
#

it's x, y, z

#

but essentially not the same as your desmos

spring haven
#

x,y,z are just labels

vale vigil
#

alright

#

it's 3 axes

#

and those 3 vectors are the basis vectors

#

corresponding to each of the axes

#

good now?

spring haven
#

sure

vale vigil
#

over here

#

Same setup, is this possible now?

#

1,0,0
0,1,0
And 0,0,1 as basis vectors

#

and those 3 dimensions are corresponding to these vectors as their basis vectors

#

is this setup possible and factual in 3d euclidean space as well?

#

just tell me a yes or no

spring haven
#

sure

vale vigil
#

cool

#

these are, solely decided by the relative directions of where u keep the axes towards

#

that's why in one set up its towards the top right (in visual space)

#

and in one set up its to the bottom left (in visual space, I know about 4 quadrants by the way.. in actual visual space these would be at top right and bottom left tho)

spring haven
#

I don't get why you're not doing this experimentation in 2D, it would make drawing the figures way easier

#

and doesn't really change anything substantial

vale vigil
#

the point being that, we need a third object

vale vigil
#

if we don't have a third object

#

bottom left, would be as top right (I mean... it would be flipped for our view, but it's not the graph that's flipped, it's our view that's flipped)

vale vigil
spring haven
#

you're just acting obtuse and degrading

vale vigil
#

this is why, you wouldn't understand it in 2d space

#

actually it's not why u WOULDN'T be able to

candid pulsar
vale vigil
# vale vigil

this just an explanation of why third object is necessary

vale vigil
#

it's a showcase that, in 3d space, if we flip the direction of the graph

#

then the position would be different

#

and we can't allow the position to be different than what we mean

candid pulsar
vale vigil
#

it's not actually getting flipped

#

but like

craggy plank
#

I’ll give it a try, are we still discussing the original question?

vale vigil
#

it's a different representation

vale vigil
candid pulsar
vale vigil
# vale vigil

look at this, over to the left side; u have x being the horizontal line, y being the vertical line (for u, this is actually 3d space and there's z also but I'll make it more comfortable)

#

and we already have the basis vectors
1,0,0
0,1,0
And 0,0,1 even though I didn't draw them they're there, and also the point is at 5,6,7 and it sticks true to being at the correct location of 5,6,7 with those basis vectors

vale vigil
# vale vigil

over to the right, even though it looks flipped, it's quite literally the same because everything in the graph is being flipped

#

but to an outside, observer, who is in the same 3d euclidean space

vale vigil
candid pulsar
candid pulsar
vale vigil
#

I already know that

#

you'll understand what I mean, hold on

vale vigil
#

because

#

the direction of axes matters

vale vigil
# vale vigil

if a person 2 talked to person 1 about the left side's graph

#

but person 1 thought it was the graph like it is in the right side of the picture

#

then person 1 would have a wrong understanding of the point

vale vigil
#

"it is not the same after flipping" Can u redefine this statement?

vale vigil
#

I see infinitely many answers that we ORIGINALLY got, from the question itself; which didn't specify the direction of the axes

vale vigil
#

the question itself literally didn't gave the direction of the axes

#

ant dont confuse the question here

vale vigil
#

but

#

these people don't talk about direction at all

#

I've been arguing here

#

for 22 hours or more

#

no one gave me a direction, they said it doesn't matter

#

BUT IT CLEARLY DOES

#

you need to know how the axes is situated even if u have the numbers of what axes is situated

#

I need this direction

#

in 3 dimensional space even more precisely

vale vigil
# vale vigil

because there's infinite directions for a point to go; infinitely different points that are gonna be located, with the same numbers called basis

#

all of the answers are ORIGINAL

#

NOTHING IS FLIPPED

#

the question needs to imply the direction, otherwise it is incomplete!!!

#

and what my purpose of making this thread is

#

to argue that, the direction is impossible to define

#

because u have a paradox of defining another x, y, z and how it would be situated to construct the line for the perfect direction

#

and more and more

vale vigil
# vale vigil

Alright, I'm gonna stop here PLEASE READ FROM HERE ANYONE WHO'S GONNA COME FORTH ON

#

I perfected my argument

#

I believe........

candid pulsar
#

okay so if you want a reliable coordinate system and basis vectors to plot your points on
then you can assume the basis vectors to be perpendicular to each other and in the directions as specified in the diagram below

#

for your convenience and to anyone with whom you're going to discuss 3d geometry with

vale vigil
#

we literally can get a lot of answers just with that

#

and by the way, we're not even changing the origin for the third object's pov

vale vigil
# vale vigil

Alright, I'm gonna stop here PLEASE READ FROM HERE ANYONE WHO'S GONNA COME FORTH ON

candid pulsar
#

just fix them in those directions in your mind

vale vigil
candid pulsar
#

what is this property of perpendicular angles

vale vigil
#

that y axis is perpendicular to x axis

#

and that basis vectors

vale vigil
candid pulsar
vale vigil
#

wouldn't they

candid pulsar
#

no.. you would have a negative sign

#

3, 4 becomes -3, -4

#

not the same

vale vigil
#

so in the new direction, the place where it should have been positive with the current directions, it would be negative, and vice versa

#

so 3,4 wouldn't become -3, -4

#

u literally changed the axes as well

#

the quadrants (positive, negative, positive positive etc..) change with u

candid pulsar
#

3, 4 means that

vale vigil
#

lemme give u an explanation

candid pulsar
#

you are using 3 times the x vector and 4 times the y vector

#

once you flip both your vectors

#

you need to use -3 times the new x vector and -4 times the new y vector

#

to get to the point you started with in this new system

vale vigil
#

@candid pulsar

#

u see this?

#

this is what you've defined

#

now

candid pulsar
#

ok this is coherent

#

go on

vale vigil
#

what if I do this?

#

do the quadrants not move along with me?

candid pulsar
#

correct

vale vigil
#

and

#

the point is numerically the same

#

as the first point

#

correct?

candid pulsar
#

say any point on the top right of the origin is the point you say

vale vigil
candid pulsar
#

and the point remains there even in this new system

vale vigil
#

it's the same numerically as in this representation where u gave, both of them are 1,2 right

vale vigil
candid pulsar
vale vigil
#

this can be an entirely new system

candid pulsar
#

the point remains there

vale vigil
#

we literally can create this ourselves

#

not required to link it with an old system

#

therefore, it is 2 systems

#

having numerically the same point

#

but they're different in direction for a third object viewer

vale vigil
#

when I drew this

#

numerically same, spatially different

#

direction MATTERS that's why

candid pulsar
#

numerically relates to numbers

vale vigil
#

the point is still 1,2 in the second system

#

it did not become something like -1, -2

candid pulsar
vale vigil
#

+1, +2

candid pulsar
#

the point denoted by what you say as 1, 2 would not be the same

vale vigil
#

It wouldn't become another number

candid pulsar
#

but two different points

vale vigil
#

Even though they'd be in different locations

#

because, we have imagined a different direction

vale vigil
candid pulsar
#

yeah since you are using another coordinate system to define 1, 2

vale vigil
#

if we imagine one single direction

vale vigil
#

we just changed directions linearly

#

And no question ever specified about directions

vale vigil
#

I appeal for any of the learned persons <@&286206848099549185>

#

to tell me how we'd define that true direction

candid pulsar
#

ok so the same way in 3d space you know that they are perpendicular but youre not sure in which way

vale vigil
#

literally both of the systems follow same properties

#

their axes are situated in different directions

#

that's it

#

they're perpendicular

#

and follow everything, like same basis vectors

scarlet sinew
#

? wtf did i just walk into

candid pulsar
vale vigil
candid pulsar
#

you can invoke the real world in this case to fix your thoughts

vale vigil
scarlet sinew
vale vigil
# vale vigil

@candid pulsar This is what u imagined, a perpendicular axis stuff

candid pulsar
#

not exactly that way

#

but those are perpendicular too i guess

vale vigil
#

@candid pulsar and this is what I imagined, keep in mind this is not the "flipped version" Of that

#

this is an entirely, original version, that I don't need that for me to generate this

#

BUT

#

if u look at the numericals

candid pulsar
#

yeah i get it

vale vigil
#

you will have literal same numericals

candid pulsar
#

numerically the same point

vale vigil
#

yeah u do now

#

and that is why

#

I argue that

candid pulsar
#

but at a different place

#

that is why

vale vigil
#

matters

scarlet sinew
#

im getting fucking lobotomized by this chat dude

vale vigil
#

none of these other people understood me

candid pulsar
#

to fix your thought

vale vigil
candid pulsar
#

so when you are trying to imagine (5, 6, 7) for now just think (5 to the right, 6 to the top and 7 towards me)

vale vigil
#

saying it's to the "right" isn't valid

#

you do understand that right?

candid pulsar
vale vigil
#

it's not

candid pulsar
#

but for your standards its more than enough

scarlet sinew
# vale vigil matters

how is that supposed to matter

im assuming that you’re sticking to the og question of “can a line exist as an equation in a 3D space”

candid pulsar
#

and you would feel better working with this till you get a good exposure of vectors and other stuff like that

vale vigil
# vale vigil it's not

mathematically if it was valid, we didn't need to construct equations for line, we could've said " Oh a bit slanty slanty over here, and a bit top left over there and a bit"

vale vigil
vale vigil
#

it matters now isn't it

scarlet sinew
#

are those fucking runes

candid pulsar
vale vigil
#

there's a third object that cares if u change it into a wrong perception of direction of axes

vale vigil
candid pulsar
#

that is why we are trying to imagine things like that with simpler and easier-to-understand real world notions

#

its not always easy to go full abstract mode

#

sometimes you need a crutch

scarlet sinew
#

basically wtf is going on here
angeryklein

candid pulsar
#

why do you even have 3d geometry in 9th grade lmao

vale vigil
#

For us, it's almost always a Euclidean 3d space

#

which is what we're talking about here

#

how do u think I got these questions without knowing any of the vectors text book knowledge?

candid pulsar
scarlet sinew
#

okay so basically your question is

can a line in 3D euclidean space be represented as an equation right

vale vigil
#

because we literally live in 3d and ur mind could think so

candid pulsar
#

what do you think you would understand in the real world

#

go to the right

candid pulsar
#

or go to (1, 2, 3)?

scarlet sinew
vale vigil
scarlet sinew
candid pulsar
#

thats easier to understand

vale vigil
#

@scarlet sinew hold one 2 minutes let me reply to this person

scarlet sinew
vale vigil
#

@candid pulsar

#

all the yellow lines (and more)

#

are considered to be "towards your right"

#

all the red lines and more to your left

candid pulsar
#

towards YOUR right

#

what is your right hand

vale vigil
#

so which one exactly is "move towards your right"

vale vigil
#

imagine it like that

#

that semi green line's center is where we are

#

so which one of the directions is "towards your right" in that yellow lines

candid pulsar
#

in the right perpendicular to you

vale vigil
#

?

#

yes but all of those yellow lines are directions of "right"

#

u need co ordinates to describe the correct right

candid pulsar
#

only one of those "right"s are perpendicular to you

#

that right

#

the perfect right

vale vigil
#

how do u explain someone what perpendicular is

#

to them?

#

hmm? maths has already done this really rigorously

#

by co ordinates

#

sure, human intuition has a right too

#

but

#

it's literally crumblingly undefined

candid pulsar
vale vigil
#

I'm not gonna argue with u anymore on what my purpose is

#

thank u

scarlet sinew
vale vigil
#

I'm going back to replying to the other people

candid pulsar
#

sometimes you are asked to guide through elementary math with rules and intuition

#

and only after you reach a decent level of knowledge are you asked to wrack your brains

scarlet sinew
#

blurple what are ur thoughts about this convo so far

candid pulsar
#

im entertained

scarlet sinew
#

im lobotomized

vale vigil
#

now

#

in which direction

#

would these vectors be?

#

basis vectors at least

#

in directions of their axises right?

scarlet sinew
#

in whatever’s positive in the respective axes?

#

ig?

vale vigil
#

yes

#

now

#

what direction would their axises be?

scarlet sinew
#

spreading out from a center

vale vigil
#

but in what way

#

HOLD ON DO NOT SPEAK YET

candid pulsar
#

yes this is a weird question but it is true

#

you cannot say what direction they are in with the English we work on for now

cyan kayak
vale vigil
scarlet sinew
candid pulsar
#

best description you can give is, x-axis is in "this" direction, y-axis is in "this other" direction, and z-axis is in "this third other" direction

vale vigil
#

they really matter

candid pulsar
#

but they are fixed in space

scarlet sinew
#

okay sure

candid pulsar
#

just that you cannot describe them with English or any other language properly

#

however, it is much easier to use words like up, right, and towards

scarlet sinew
#

then i expect you to define them mathematically

candid pulsar
#

so thats what we go with at the start

scarlet sinew
candid pulsar
#

and then let you in the details once you are comfortable

scarlet sinew
#

yea

vale vigil
# scarlet sinew in representation

they legit matter... if they don't, I can pick 2 answers and say " Hey these look like 2 different lines even in co ordinates and positions to me, so the equation didn't tell me which of the infinite lines I should pick even though it told me something like the measurmeent, it still led me to nothing than the original question: which of the infinite lines am I describing"

candid pulsar
#

well yeah they are fixed in space

#

i just

#

cant say HOW they are fixed

#

and the best to do as consolation at this point is

#

convention

#

like what ive been saying

vale vigil
candid pulsar
#

you can take one of them

#

and work with your problem

vale vigil
candid pulsar
#

the easiest to go with

vale vigil
#

I thought u were real and the truth and rigoroys

candid pulsar
#

is convention

vale vigil
#

is this all u got? a rough "idk"

candid pulsar
#

sure if you are a multidimensional god

vale vigil
#

you are not the one to define human capacity