#help-23
1 messages · Page 54 of 1
Same
was i meant to half 6/5
Be careful of what you're doing, show a couple more steps to see exactly what's going on
You have an extra square
Yes
OH YEAH
thanks alot
ok ill see how that goes
i make the lcm /20 right
guys now what
oh
19/20
@compact ferry
@lean otter Has your question been resolved?
sfe
Mehdi_Moulati
@lean otter Has your question been resolved?
@shut inlet how did it go from -5+24/20 to 19/12
i made a mistake , 20 instead of 12
$5x²+5x +6 = 5(x+\frac{1}{2})² + \frac{19}{4}$
Mehdi_Moulati
Mehdi_Moulati
@lean otter Has your question been resolved?
where does 30 come from
. 5
we r gonna fail
exams
well
i am
imma start revising friday
have to go cousins house
tomorrow
@lean otter
😭
but i only have to revise science and maths
I have to go somewhere tmrw too
ima revise in their house
I'm not sure
if u X 5 won't everything be timsed by 5
6/5 goes to 30/5
Ye - it's all distributed
I'm gna need way more practice on this
thanks for the help
do you suggest any apps
to work out completing the square
Just Google "completing the square practice problems"
they don't show working out unfortunately
I tend to forget this step and find the LCM and add immediately, any tips?
In that case you can look it up on YouTube
Just Google what you need, it's there for you
You can find the least common multiple of the denominators and add them before distributing
One is not better than the other
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Can someone please help me with this kinematic question?
,rotate
@rugged dragon Has your question been resolved?
I don’t understand anything 😅
Like where to begin at all
Or how to tackle questions like this
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Why is this highlighted portion negative?
Does it have to do with F(r) vs F(r + dr)?
Given that dr is really small, can we not just say that the force for that line segment dr is a constant F(r)?
It’s just a vector field, we aren’t given any information as to the direction of F
Regardless of what direction it points, whether it’s toward or opposite dr will be captured by the dot product, so I’m unsure of why the - is there to begin with
Any opposite-pointing vectors will have a negative sign introduced via the dot product itself
maybe coz it says work done "against" a force
they do mention that the direction of the integral along the curve must be specified
and if the direction is reversed u multiply again by -1
That’s for a general line integral, I’m pretty sure
I’m not sure it’s work done against a force
Regardless, it doesn’t impact the rest of the section
But thank you!
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I got 15/32 by finding the probability of X, and the probability of Y and then multiplying X and Y together, however I did not get the answer. What did I do wrong?
confusing setup and confusing question
the table seems to show the fraction of novels sold to each gender per novel type...
and you seem to be asked for two numbers, yet the answer options only list one...?
i'd skip this problem and seek clarification as to what actually needs to be done @hard canopy
I’m pretty sure they are asking the probability of X and Y together, like the intersection of X and Y
Is that better?
so the probability that a randomly chosen novel was both a teenage novel sold to a man and a children's novel sold to a woman?
that sounds like zero to me.
as i understand it, the entries in the table correspond to disjoint categories of books sold...
yeah, you can’t be male and female at the same time
more importantly a novel cannot be both children's and teenage
Yeha I’ll just close this channel since the question is confusing, I’ll ask my teacher, thanks
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How do you do this:
proof that 5^(n) +3 is divisible by 4 for all positive integers
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whered i mess up
Line 3
is line 3 including the question
or line 3 of the workng
oh
what did i do wrong
ohh was it the halving
Expand your squared term and see if it's right
alright
im not that good at expanding leme try
uhh i feel like im expanding wrong already
what do i do with the square
okay i got that
now i gotta minus
acc ima just redo it all 😭
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I intuitively know it’s C. How do I show it?
you mean your friend told you the answer but didn't want to tell you the explanation
no its quite obvious intuitively that its C
No, A and B are obviously wrong. D has periodic functions which have no reason to converge
ok
How is it intuitive that it is C ?
because its not A B or D
Check my previous message. It’s the process of elimination 😄
bruh
Positive sequence implies lim a_n = 0
and for C the only way its divergent is if a_n would approach a vertical asymptote at 0
Not sure if that’s any use
but tan(x) has no vertical asymptote at 0
probably is
Positive sequence approaching 0 implies a_n is also decreasing
doesnt have to be decreasing
Yep, nvm. It can be oscillating down too
like for A, just take the sequence
1 1 1/2 1/4 1/8 1/16 ... and it contradicts, for B take the same sequence and it doesnt even converge and for D i think the same sequence works too, it gets really close to zero, so cos gets close to 1 and sin close to 0 and it doesnt converge
I’m kinda looking for something more rigorous
do you need to directly show C is correct>
yeah, but for anyone wondering why its intuitive
because it seems showing A B and D are false is easier
i think showing C is more interesting
for sure
I technically don’t but I honestly don’t feel good about that. What if a b and d werent so obv wrong?
true its good practice
i think you can do it with comparison test
is there a nice iff test
tan is continuous, i think I could also show tan(a_n) is diminishing
tanx < x for small enough x even
dont think so
for negative x yes
Isn’t the maclaurin for tanx = x + o(x^3)?
,w series tan(x)
For positive x too look 😛
thats 2x
,w plot x vs tanx
I have a question, what if one of the terms of a_n is pi/2 won't that result into non convergence of tan(a_n)?
it would make the whole series undefined
cause tan(pi/2) diverges
not defined at pi/2
Hm, so anyway. 2a_n does indeed also converge, and tan(a_n) is definitely < 2a_n
I think comparison test does work
Eh, at the very least I’m convinced. Thanks @compact ferry && @lean otter
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how do i do this
ping me if you know pls
part a
if a is the real part and it equals 1/2 how can a/a = 1/2
a/a should just be one
Given that the real part of z is 1/2, find*
The real part of z is what
Ok, put z in the form x+iy
so :
a + ib = (a+2i)/(a-i) ?
nah
oh wdym
Put it in the form that show us the real part and the imaginary part of z
x+iy
or a+ib, whatever its just variable
bro just destroyed algebra
$z = \frac{a+2i}{a-i}$
Herels
we have on the denominator so we need to rationalize it
$z = \frac{(a+2i)(a+i)}{a^2 + 1}$
Herels
well u can just multiply z by (a+i) /(a+i), separate the i's and comparr it to 1/2
$z = \frac{a^2 + 3ai - 2}{a^2 + 1} = \frac{a^2 - 2}{a^2 +1} + i \frac{3a}{a^2 +1}$
Herels
yeah that
$\frac{a^2 -2}{a^2 +1} = \frac{1}{2}$
Herels
$2a^2 - 4 = a^2 +1$
Herels
yeah
ah they said a>0
yeah
Thank you guys for helping me understand🙏❤️
and the argument is atan2(im(z), re(z))
nobody ask for it
np
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How union of two vector subspaces is a subspace of the vector space, iff one of the subspaces contain the other?
can you be more clear about the assumptions 
u want proof
The proofs aren't given here. I don't understand these facts.
Yes
@slow fern Has your question been resolved?
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how is 288 and 342 obtained?
How is 288 and 342 obtained as solutions
arcsin(sin324)
which gave me -36
and then i did 180 - -36
to give me 216
then i did 216 + 3
oh wait#
i got 288, 162 and 108
how do i get 324
you'll get x = 162 + 180k or x = 108 + 180k
when you work with k = 0 and then k = 1 you'll get the 4 solutions
yeah that can work as well
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how can I study the parity of a function?
by calculating f(-x) ?
check whether it is symmetric about the x-axis and/or the origin
if the graph is symmetrical according to the origin coordinate, your function is odd
if the graph is symmetrical according to the y axis, your function is even
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Anybody going to use this channel?
Micos?
I going to move
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hi!
its too difficult
@prime cobalt Has your question been resolved?
ohh it’s difficult for me too 😭
is it a college exercise ?
yes preparation paper to prepare for A levels
not college yet
entering university next year
good luck
ty!
this is legendres formula if you want to look it up
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ty!
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managed to get it :D
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sup
@quasi bison you’ve helped me yesterday so I have pinged you to see if you’re able to help me with this today
first part
just calculate the limit @frosty fox
1-2/(k+3) tend to 1 when k tend to infinity
so :
lim a_k when k tend to inf is ln(1) which is 0
*Using that log is continuous
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polynomial division, then quadratic formula
how exactly?
hi!
sup
hm
since you know 2z+5 is a factor you can use 8z^3 +125 = (2z+5)(Az^2 +Bz + C)
C is 25 here
You can multiply z by a third root of unity to get another solution
then you can compare coefficient of z^2 maybe
uh
And the square of said root of unity
whats a unity?
A unity is 1
"roots of unity" means the solutions to x^n=1
i didnt learn that method
also whats this
Polynomial long division
well a bit of a nonstandard way to write it down tho
how you know C is 25??
oh dang
if we want another few overkill methods, you can also view 8z^3+125 as a geometric sum
I compare coefficient of z^2?
uh lmao nahh im good
oh haha sorry!
yes
how?
yay!
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really quick question: how do I factor (10.sqrt(2))^2?
?
Well it's already factored
Expand then
yes
Remember
You can distribute squaring if it’s multiplication
$(ab)^c = a^c b^c$
exactly
VulcanOne
ohh so it's 200?
alright, it didn't matter anyways because I got lost in the problem and realized I didn't have to figure that hypotenuse to solve it
regardless, thank you
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✅
here's the problem solved, by the way
I think it's correct
I had to figure out the value for the shaded areas, in case it wasn't clear
That’s just half the original thing
Wait are you sure
Nvm
You got it
But yeah the shaded region is half the entire thing
don't get misled by my drawing, the length of BS is 10.sqrt(2)cm
don't brain shut for me, it's not worth it
but yeah I solved it again and it gave me the same result
so I think I got it right
now I can close this
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why is m+1 choose 2 the same as m(m+1) / 2
Use the formula for binomial coefficient
U choose first item from m+1
Then second from only m
So m*(m+1)
But u can choose second firstly, then first secondly
So u divide it all on 2
Cmon
Classy handshake problem
Google handshake problem
i dont really understand tbh
I can explain it for u but tommorow
Think about n!/(n-2)!
yea ik u wanted to go to sleep thats why i asked in pub
Everything below (n-2) cancels out
Thats formally good way but imo wrong way to think
Because it both in the numerator and denominator
Yeah but
I said there were two ways before
This is the first way
Understandable so far
And no it’s not the wrong way to think
So then you just left with n(n-1)/2!
Which is just n(n-1)/2
wait i need to reproduce that step
It’s not wrong to think this way
So right now you have n!/((n-2)!(2)!)
So when having
n!
(n-2)!
it will become
n(n-1)
2!
?
Which is n(n-1)(n-2)(n-3)…/((n-2)(n-3)…(2!))
No
It will just become n(n-1)
I forgot to include the 2!
That’s also there
i forgot to do the faculty after 2
Factorial
It is cause it kills developing special kind of intuition destinated to task bkit probablity
No
It’s cool I just didn’t want you thinking it was faculty 😂
😄
ok so to recap this
thats what i tried to reproduce here
but i get 1 as denominator due to shorten. how do you get the 2! ?
@mortal pawn
In the definition of choose
It’s n!/(n-2)!2!
That’s where the two comes from
Now if you want to
You can think of it this way
N choose 2 is like choosing 2 items from a set of n things
With no preference for order
n(n-1) is the number of ways choosing 2 items with order mattering
How many ways can you order two things
Only 2 ways
Yep
👍
so i need to devide n(n-1) / 2! by 2 ?
i got one question to the stuff above
Yeah
It kills
Why is N Choose 2 no preference for order
but
N(N-1) does have a preference
N choose 2 just is that’s the definition of choose
ok ok
N(n-1) is like
First I’m going to choose 1 of n items, I have n choices
Then I will choose 1 of the remaining n-1 items, I have n-1 choices
The thing is
That you can choose the saim pair twice
For example I can choose A first and B second or B first and A second
ok and to connect this to your previous explanation, if i just want one of n items, i will divide my possibilities n(n-1) by 2 right?
oh damn i finally understood it
after writing it all down and put it together it made sense
big thanks @mortal pawn
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is this for all n greater or equal to 1
yeah
Yes
how do i prove n=1
plug it in
does 0/12 prove it as being able to divide by 12
definition of divisibility
ye im confused by these notations
a is divisible by b if there exists an integer q such that a=bq
oh i understand
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\begin{tikzpicture}
\draw[ blue, very thick] (-4,-4) -- (4,-4);
\draw[ blue, very thick] (-2,4) -- (-4,-4);
\draw[ blue, very thick] (-2,4) -- (6,4);
\draw[ blue, very thick] (6,4) -- (4,-4);
\draw[ blue, very thick] (4,-4) -- (2,4);
\draw[ blue, very thick] (-2,4) -- (0,-4);
\draw[ blue, very thick] (-3,0) -- (6,4);
\draw[ blue, very thick] (-4,-4) -- (5,0);
\node[ scale = 0.8pt] (a) at (-4,-4.5){A};
\node[ scale = 0.8pt] (a) at (0,-4.5){E};
\node[ scale = 0.8pt] (a) at (4,-4.5){B};
\node[ scale = 0.8pt] (a) at (5.5,0){F};
\node[ scale = 0.8pt] (a) at (6,4.5){C};
\node[ scale = 0.8pt] (a) at (-2,4.5){D};
\node[ scale = 0.8pt] (a) at (2,4.5){G};
\node[ scale = 0.8pt] (a) at (-3.5,0){H};
\node[ scale = 0.8pt] (a) at (-1,0.6){S};
\node[ scale = 0.8pt] (a) at (1.5,1.4){R};
\node[ scale = 0.8pt] (a) at (-0.2,-1.4){P};
\node[ scale = 0.8pt] (a) at (3,-0.8){Q};
\end{tikzpicture}
Anik
In ABCD parallelogram E, F, G, and H are the midpoints of
AB, BC, CD, and DA respectively. Area of ABCD is 30 sq.
unit. Find the area of PQRS.
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hi!
this might be a dumb question haha but for part (a) would you use horizontal line test?
probably not if it’s asking you to show it
strictly increasing/decreasing is enough
oh okay ty!
probably worth noting that’s only enough to show it’s injective
well actually that might be all it expects cus it doesn’t mention anything about a codomain in the question
inverting a function without a codomain 

well the codomain has to be its image for it to have an inverse, right?
@prime cobalt Has your question been resolved?
it doesn’t say that’s the case but it’s whatevs
i just meant like
if i am asked to show something has an inverse
i would think that’s something i need to show
showing bijection without a codomain 
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How to find the $dx$ for any $d\theta$ from a equation of a circle? How to do that with an irregular shaped closed curve like eclipse, parabola, hyperbola etc.
Anik
@wind fog Has your question been resolved?
dx and dθ don't make sense in any this context.
guessing a tiny change in the x position and the angle value theta but still 0 sense
Perhaps if you write $ x = r\cos(\theta)$ you can find smthg
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Is the formula for the number of self similar objects in a sierpinsky pyramid 4^n?
@dark ginkgo Has your question been resolved?
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How to solve this problem 18
@prisma urchin Has your question been resolved?
What got blacked out
You can use this rule
can i ask from here, what the steps are
sorry @prisma urchin
I did word blacked
The word is "is"
Probably
I don't know how to translate it
Fist log given and 2nd find out maybe hhe
What steps
It's just one of the identities you learn, or at least I learned
I haven't gotten around proving it, but it probably ain't hard to prove
It just becomes dln(c)/(bln(a))
@prisma urchin Has your question been resolved?
Change of base will prove it lol
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what does it mean by the "the nature of" in this question
the nature of the question is whether the answer is going to be real, irrational, or complex im pretty sure
yes its the count of real zeros
thank you
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Just doing through some lectures at the moment and my LA really needs some work, can someone help me understand the orthonormal basis, I have examples and just would like to verify before I go ahead with this example of orthogonal projection in R3
The bit in red?
Yes!
Taking the dot product and it’s generated norm, you can see that e1.e2=0
First off can I ask you some questions about the orthonomal basis?
And that the norm of each element is 1
hehe okay so
As you know my understanding of LA is weak and my understanding of the basis stuff is even worse but in this chapter I was introduced to this definition of "orthonormal basis"
Here is the definition I have been provided
First off, the inner product of the uniterary vector (I think that's what they call it) what is it?
I am a bit confused on the inner product of vector spaces in general since we have used the inner product for other stuff such as polynomials and I haven't see wnat the <> actually encases
However, looking online apparently you're supposed to just dot it ?
Not sure what you mean there, could you elaborate please?
Well there are many different inner products, the dot product being one of them
So I am basically a bit confused on the definition, what is < > I guess
Looking at the definitions in my workbook, an inner product on a vector space is a function that takes each ordered pair of elements V to a real number
bit doozy looking at that
But you can define an inner product over a vector space in many different ways, they just have three properties they need to satisfy
the main get away is just, an inner product takes some ting to a real number denoted by <u, v>
in the photo i provided before, it just says <ei, ej} = little delta
or is that epislon, i havent really been taught the greek symbols yet
like they havent really defined what the operation is right?
They just say that if the result is little delta which is either (1 or 0) then it is a orthonormal basis?
Maybe my understand of vector space and inner product is weak as well
Well yep, the inner product is just a map from your vector space to the scalar field you’re based on
Any map on a vector space that satisfies those is an inner product (though some looking weirder than others)
god damn
(When you’re in the reals, the complex conjugation has no effect btw)
LAMOOOO WHAT IS THATTTT
But basically, given an inner product
You can talk about orthogonality and orthonormality
Perhaps you could elaborate on definition 4.1
I'm assuming the two cdots are operations?
Namely addition and some sort of multiplication?
Basically those dots are placeholders really for elements of the vector space
Side note
Takes two vectors and spits out a scalar
That definition stuff has nothing to do with like fields in general right
Like the groups and fields
Well I guess, your vector space is defined over a field, but other than that…? In this case we only really care about the real numbers and complex numbers (ignore any other field for now!)
Okay I concur
Okay so the inner product space just has to have those three hold
I'm assuming 4.1 is some sort of expansion property
4.2 is maybe additive properties
I have no clue waht 4.3 is but maybe that has something to do with the cauchy inequality? nvm
Yep, linear in your first component
(Though note that some people choose to be linear in the second component)
Conjugate symmetry
(Over the reals, that’s just symmetry as the conjugate of a real number is just itself)
I see I see
The inner product of an element and itself is a nonnegative real number, and only zero when it’s the same element
That property then helps with defining a norm from that
These are the "identities" provided from my textbook
I am assuming some of these are just an over simplification of your versions
To make it more digestable for students?
In particular, (I2) and (I3) make up my (4.1), (I1) is my (4.2) (but for real numbers), and (I4) and (I5) make up my (4.3)
I see
Generally I think people find it easier when you break it down like yours did
haha yeah
For me I’m more used to just jumping in and doing the linear combinations right away, but that’s with the time I’ve been doing this I guess
So just to clarify with the "naming" of these identities
(1): Inverse? (2): Expansion? (3): Scalar multiplcation? (4): idk? (5): idk
Like is there a document or resource online to search for, for the names
After doing some maths I think it's starting to get important to learn them since I have been seeing these rules since algebra
Although i think they are called axioms not rules
1 is symmetry, 2 and 3 linearity, forgot the name of the last two
Let me check that for you
Positive definiteness
Ah, to-may-toe, to-mah-toh 🍅
Same things, different names 🤷♀️
haha yeah doesnt matter
was just curious i guess
Anyways why were we talking about this again
To introduce orthogonality?
Yep, so with an inner product defined, you have a norm automatically generated from that inner product, so you can talk about distances
- you can then define orthogonality with respect to that inner product
wait actually
It is important to really get the basics of like
vector spaces etc to go further
ah nvm ill just read it later
I think my main question was like what <> was and now I think you've cleared up the fact that <> just denotes inner product
Now, it's obvious that we have certain axioms etc but lets go back to the definition
Yep, that’s pretty much it, some inner product you’d have defined
I am basically confused because <ei, ej> = little delta
If the inner product of the ei and ej is equal to either 0 or 1 then it is a orthnormal basis... but like
what is <ei, ej> actually? Does it have an operation or? What are we doing two these two vectors
“The inner product between any two vectors [in that set] is zero if they’re different, or 1 if they’re the same”
oh i should of read the definition properly
Just the inner product between e_i and e_j
But what is the inner product? From definition its a function which satisifes the 3 properties?
But what is the function doing I guess
Basically that, to be fair I’m not the greatest at explaining the exact concept of the inner product (just some of the properties it has tbh)
Like e.g. the fact you get a norm out of it and the orthogonality
Here is a definition I found online and nowhere does the definition from my book mention the dot product of two vectors any where
but from what I got from this definition is that
given a set with vectors u1, u2, ..., un
The dot product of any of the vectors (if theyre different as you mentioned) should give 0 while if the dot product of any of the vectors within the set where they are the same should give 1
Correct me if I am wrong
That’s for orthonormality
(For orthogonality you just need the inner product of any two different elements to be zero)
Maybe we consider an example
Oh yeah this is the Gram Schmidt stuff you’re doing now isn’t it 
Just remembered you said 
If we consider a set {(1, 0, 0), (0, 1, 0), (0, 0, 1)}
Well this was given in the lecture among other examples, its said that this set is an orthogonal basis
How should we go about showing it
Matter of fact, it’s orthonormal
You have the definition of the dot product somewhere right?
(Just cause I’m on mobile atm so a tiny bit harder for me to fetch stuff)
Yeah um
I dont want to pull it up but the dot product of two vectors is like
well in this case
(1, 0, 0) . (0, 1, 0) = 0
(1x0) + (0x1) + (0x0) = 0
Now I just "assumed" that the dot product is commutative (I think is how you say it)
So I just need to consider the following combinations
(1, 0, 0) . (0, 1, 0) = 0
(1, 0, 0) . (0, 0, 1) = 0
(0, 1, 0) . (0, 0, 1) = 0
I should only need to consider these three to show that this set is indeed, orthonormal
(+ it’s easy to show symmetry of the dot product)
That’s orthogonality
For the “normal”-ness, check the norm of each vector
Take the dot product of each of them and itself, if you get me?
Remember, orthogonality is just that the inner product of different things is zero
Orthonormality requires both orthogonality and also that the norm of each thing is 1
You’ve done the orthogonality bit so far, if you see me?
to check the normal ness, check the norm of each vector
um give me sec
uhhhhh
like the sqrt(v . v) stuff?
ohhhhh
||v|| = sqrt(<v,v>)
this??/
oops
$\norm{v} = \sqrt{v\cdot v}$
ohhh
chartbit
the norm of the inner product
if the inner product is 0 then the norm is just sqrt(0) which is still 0 so then it still follows with the definition
need to reread everything you said with orthonormal and orthogonality later as well lol
Well, the dot product of e.g. (1,0,0).(1,0,0) is just 1, no?
Similar for the others
oh so besides the fact I need to check for the combinations of others
i need to check 3 combinations where the vector is the dot product of itself to check if the norm of the dot product is 1 as well?
Yep, you need to check each of the ones with themselves (but that’s easy once you spot it in this case)
I see I see
So to check the orthogonal set of vectors (orthonormal) we can just consider the combinations where we get all the vectors and dot them together then find the norm, they all must be equal to 0 in this case, the second case is find all the combinations where we dot the vector itself and find the norm, they must be equal to 1
If they do not satisfy these two conditions, the set is not orthonormal...
Yep, if you fail for one of them, you’re not orthonormal
For orthogonality, you just need the first part
Another thing is that any orthogonal set of non-zero vectors is automatically linearly independent
(In particular, an orthonormal set is linearly independent)
But that’s for another time I guess 
I'm going to skip the decomposition and orthgonal project theorem at the moment and do this example
I mean the proof for it
Yep, do the rest later 
So I am assuming to use this orthogonal projection theorem, we would need the set to be an orthonormal basis
Hmmm, let me check that, I don’t think you do, unless I’m mixed up?
uhhh i am not sure either LOL
Actually I think you do, at least from my quick browsing haha
Pain to try and look through notes on mobile when they go through so much 
Yeah so i think the main thing first is that
I would like to check the set if it is indeed an orthonormal basis
But we are given a span not a set
Well, it’s the span of a set 
So can just do what we did before
Take the vectors of that set and work with those
(Which here, orthogonality is easy!)
Heyyy @shut inlet
Can you believe I haven’t gone to bed yet 
oops sorry
WHAT

I just woke up 2 hours ago @junior smelt
😆
Yep basically that
Like
(0, 0, 1)
any second vector
at the third entry if it is 0 then it will be 0 anyways
or (1, 0, 1)
as long as the second vector is just (0, x, 0) then it is easy to compute ?
Basically, that’s the idea, you have (?, 0, ?) and (0, ?, 0)
so we keep saying orthogonality
Take the dot product, you see what happens haha
Is that the same as orthogonal?
Yep yep
Ah okay I have checked it is indeed an orthogonal basis
thats it for today
projection and gramm shitmz tomorrow
Goodnight and thank you @junior smelt !
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i know it's either b or c
it’s d??
so
the only way
well
the best way
is put ur pen on a point and rotate it yourslef
either b or d*
yeah and i rotated it all the way until b would be on the top and it seems like it would be either b or d
so its
it cant be B
bc if you rotate a positive shape on a graph 180
it becomes fully negative
lemme draw it
for you
@solemn kestrel do you know
rotational rules
it's d
ok
this on is a lil different since we count the distance from the point but idk which point
wdym a1
is being translated
yes
oh you mean like A'
yeah
i thought we count the pre image
in an exam it would be A1 and !2
to the image
?
which one is the orignal shape
the one on the right
I’m p sure this is actually 6 to the left
oh?
You wanna check how to move A to A’
Moving only 2 to the left just takes A to D’
ohhhh
It's not rotational
yeah thought so
im sure it's either c or d
not much really
Why would it be vertical?
the translation is sideways
and is vertical or horizontal sideways
horizontal
i've been stuck on this one for some time idk what to do if anybody who knows how to do it can pls help
i don't understand
does it say they are similar
it just says two trees are planted next to eachother
You have idea about how shadow forms?
not rlly
It forms when an opaque object comes between the path of light
This much you must be knowing
The angle at which light rays fall on tree 1 should be same as on tree 2
the clsoest that would be is 3.6
Through the given data you can relate their height
What's with this closest
It's exact
Theoretically
oh
