#help-36
1 messages · Page 78 of 1
so you forgor.
basically
do you not have any notes either?
P(A n B) = P(A) * P(B)
this is the definition of independence for the events A and B.
oh
compute the left-hand side. separately from that, compute the right-hand side. check whether or not the two results are equal.
well P(A) = 1/2 and P(B) = 1/3
ok, and what is P(A n B)? and most importantly show how you get the value.
bc there is a right way and a common-mistake wrong way.
if they are independent then it is 1/2 * 1/3 = 1/6
that's IF they are independent
you said "if". You dont know that
you do not yet know that they are.
so what should i do beforehand
you must find P(A n B) without assuming their independence.
first figure out what A n B means as an event.
for this you will need to use your brain, sorry
P(AnB) refers to the probability of it occuring at the same time?
P(AnB) refers to the probability of event A and event B occuring simultaneously
sure does.
but you need to
figure out what A n B means as an event.
like what does it mean for event A and event B to occur simultaneously?
for it to happen at the same time? 
not sure
what dice rolls fall under event A?
the numbers need to be even
list them.
2,4,6
if the dice rolls a 5 or 6
list them
5,6
so then which rolls fall under both events at once?
6
6 and only 6?
yes
1/6?
correct
that matches with P(A) times P(B).
so these events are independent.
"it"-overuse again, unfortunately.
what would be the dependent definition?
two events are dependent if and only if they fail to be independent.
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Is this right? Do I find the union of their domain? Because it is +
you want the intersection of the individual domains, not union
oh okay okay but how do i right the final answer in interval notation
well first identify the intersection from what you drew
should i still use the 'U'?
only for the domain of the first root,
but for the intersection of the domains, no
$\cap$ for intersection
ℝαμΩℕωⅤ
oh why?
inequalities don't work like that
the interval notation you have below is correct though
(-inf,-1] is representative of x<=-1, not x>=-1
how does the inequalities work?
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Every bounded sequence has convergent sub sequence
Can anyone give me a perfect example for understanding this statment
what counts as a "perfect example"
Yeah the issue is any example.isnt going to he very enlightening, someone is just going to give you a bounded sequence and a convergent subsequence, so what? The power of the statement is that no matter what the bounded sequence is, there will be some convergent subsequence, even if we don't know what it is
Any easy example so that i can understand
(-1)^n
1/n...it is bounded sequence right?
every convergent sequence is bounded
Because it's limit is 0
So in this example it is bounded by [-1,1]
So what will be convergent subsequence in it?
Sorry. I am non English speaker
not bounded by (set)
Now please simple this thing
the constant sequence 1
yes
do you mean upper and lower bound?
Yes
bounded means that |a_n| <= M. so you take care of both upper and lower bounds with a single number
if numbers are bigger than -47 and smaller than 93, then |a_n| <= 93
so you just need one number
no
the sequence 1/n is bounded by 1
it doesnt even include a constant subsequence
it itself is a converging subsequence
which converges to 0
the sequence (1/n) also has its subsequences, but they all converge to the same number 0, to which the sequence (1/n) converges
$a_{n}=\frac{1}n{}\\\text{examples:}\\a_{2k}=\frac{1}{2k}\longrightarrow 0\\a_{k^{2}}=\frac{1}{k^{2}}\longrightarrow 0$
Joanna Angel
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hi
i got a question in discrete math
is {1} ⊆ {1, {2}}?
i thought yes but the answer key said no
AK said No, because {1} is a set and there are no sets as elements in {1, {2}}
but i thought
{1} is a set with element 1
and {1,{2}} is another set
That is true
and it has the element 1
ig the answer key is wrong lol
{1} does not belong in {1, {2}}, but it is a subset of {1, {2}}
that is true yes
just threw me off
that the answer key said that
ig they made a mistake
alr thanks
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What exactly is the benefit that is realised from the fact that the eigenfunctions of a Sturm-Liouville problem are complete with respect to mean convergence as compared to like being complete with respect to pointwise convergence 
i just want some clarification on this
pointwise convergence isnt that strong
and I mean its always nice if the convergence fits with your topology
ig because ur set of eigenfunctions are only continuous on 0 <= x <= 1?
oh wait i guess like
eigenfunctions that are complete with respect to mean convergence are complete for the set of functions that are square integrable on 0 <= x <= 1
and the set of square integrable functions is much bigger than the set of continuous functions
i assume
ok thanks
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can someone explain some machine learning formulas to me in an easy way
@snow solstice Has your question been resolved?
no
@snow solstice Has your question been resolved?
@snow solstice Has your question been resolved?
Does that help?
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Im a little confused on this question
so at first I found cylinder volume, divided it by 2. Found sphere volume, and added that to the cylinder volume. I realized this was wrong as it wants how far the water rized
So then I found the volume before the sphere was dropped (cylinder volume divided by 2). Then found the volume after the sphere was added (sphere volume + original volume). Then bc it asks how far the water level raised, I did the volume of after the sphere was added, subtracted by the original volume. I get 26.1279
However, the answer key says 6.8cm which doesnt make sense
I was wondering if one of you could confirm
@spring depot
man
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Hey, im taking a look at this theorem in my notes , and in the proof there are some steps that are confusing me a fair bit, would anyone be able to explain them?
so for y' = f(x,y)
what is the cause for introducing s in 3.5?
and where tf does y0 come into play in finding g(y)
Its FTC in reverse
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how would i Know the b in (a+b)^2 is a complex number
i could do (s+1/2)^2 +7/4 but i need to rewrite in laplace form
I need to rewrite (s^2+s+2) in the form (a+b)^2
why?
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Hello
What step are you on?
1. I don't know where to begin.
2. I have begun but got stuck midway.
3. I got an answer but I was told that it's wrong.
4. I got an answer and would like my work checked.
5. I have a question about someone else's work/solution.
6. I have completed the problem and don't need help anymore. Thank you.
7. None of the above
1
Simplify into simplest radical form
Oh yeah I got it
I have one last one
I am on level 1
??
.close
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How do I find the reflections of points A,B,C in respect to the plane x+2y-3z=0? (plane acts like a mirror)
ABC are (1,0,0), (0,1,0) and (0,0,1)
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How would I do this?
I know that I can say that say one side is x
So second would be x + 9
area = (x) (x + 9)
Oh oops-
But idk what to do after I get x^2 + 9x
Should I convert it to vertex form?
Oh I forgot teh area existed
You know the area
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Can anyone help me with this?
The task states
Show that the line h through the points P(0/12) and Q(13/4) is parallel to a tangent to the graph of f at a point (u/f(u) for 0<x<4
And idk what im supposed to do
nvm i had an idea
turns out
it was rigjht
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Need to find all the asymptotes of f(x) = x/lnx. x>0 and
x |= 1. First vertical: should i calculate the limit in 0? The horizontal: limx->+inf x/lnx [inf/inf] = lim x->+inf 1/1/x = +inf
So no horizontal
Lastly diagonal: a= lim x->inf x/lnx/x = 0
b also will be 0
That mean that diagonal is y=0?
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Let G be a group. is $H=\left{ g^{2} | g\in G \right}$ a subgroup of G?
Suppose H is closed under the operation of G. Let $a\in H$ then $a=g^{2}$, $aa=g^{2}g^{2}=g^{4}$, thus $aa\notin H$ therefore H is not a subgroup of G.
marawrdr
is this correct?4
(g^2)^2
H contains all elements which are the squares of some other element
Naturally, g⁴ is a square of something. So, it's in H.
I know its not a subgroup so i have to show one of these
- Show that the identity is not in the set.
- Exhibit an element of the set whose inverse is not in the set.
- Exhibit two elements of the set whose product is not in the set.
I know 1 is a no go since the identity is in the set
2 follows from 1
so all i have to work with is coming up with two elements of the set whose product is not in the set
Why do you think it's not a subgroup?
(You may want to specify an actual group if you want a counterexample)
intuitively idk
it must not satisfy one of the conditions for a group
but its notclear which one
(If G were commutative, you would have the result true, so there's that...)
It must not be associative since theres an identity and each element has an inverse
Damn you really do have to grab a non-abelian group as a counter-example, huh? That's kinda ugly
Theres this
but i dont even know how A4 relates the subgroup in question
@abstract moth Has your question been resolved?
See choosing specific counterexample of a group: they're using A_4 as their group, and the hint below is that you can find two squares such that the product of those squares is not itself a square
So when they show that H is not a subgroup of a specific group, that means in general H will never be a subgroup
?
Well it shows that it's not always gonna be the case that H will form a subgroup of a general group G (as above there are some exceptions, but it's not true for all groups G)
@abstract moth Has your question been resolved?
I see, thats what confused me, its says let G be a group as if it was any arbitrary group, thats why it didnt even occur to me that i should find a specific group
i thought i was supposed to show that in general a subset of that type will never be a subgroup
Yea it can be a bit confusing, whether their intention is that "there's at least one counterexample" and "it'll never work" 
At least for this one it was slightly clear that it's about a specific counterexample (in fact, you could think about the trivial group, where the subgroup is basically itself(!))
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I typed out a question in #help-28. I need it to unlock to access it again, so just recycling channels. Sorry for the spam & ignore
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hey
i am working on a simulation problem
i work in python
i have a list/array/vector
ordered = [0,1,2,...,N]
this means, this vector has N+1 entries
now i want to shuffle the entries of this vector around
but the problem gets difficult because:
-i want to not have 1-cycles, as in ordered[i]==i
if we for example have the array Arr=[0,2,1]
then Arr[1]=2, Arr[2]=1
BUT Arr[0]=0
i tried to solve this with minimal recursion, but that gets out of hand quickly
so i am looking for a mathematical way that is efficient
you could just generate a random permutation and reject it if it has a fixed point
yeah that is what i tried
but that adds recursion
when things get large, it makes it slower
but i think my problem lies somewhere else
i tried to make it more efficient but i think i made an oopsie
this is the unholy junk i wrote
only 3?
if the array gets large, the amount of attempts should increase as well, no?
about a third of all permutations dont have a fixed point
oh
no
huh
in general it converges to about 37% of permutations have no fixed point
which really isnt that bad
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hey
Do you know how to solve an ODE of the form:
$\frac{dy}{dx}=f(x)g(y)$
Max
That's the easiest way IMO but there is another option
Have you seen how to solve ODEs of the form:
$\frac{dy}{dx}+f(x)y=g(x)$
Max
What topic is this from?
what do you mean?
Am I cooked
Wrong channel bro
Like what are you currently studying?
Because this could feature in like 3 different topics and so I don't know what hint to give you lmao
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u can break them down into 2 fractions which makes it easier to solve
(3-18/x) / (x-6)
like this
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Hi 🙂
A statistics/R question. I'm trying to understand what and how does this function work. Can someone explain?
For convenience:
This function returns the value of the__** inverse cumulative density function (cdf) of the binomial distribution**__ given a certain random variable q, number of trials (size), and probability of success on each trial (prob). And with the use of this function, we can find out the pth quantile of the binomial distribution.
Under this example, we are using the qbinorm function to get the 19th quantile of a binomial distribution with 30 trials with the prob of success to 0.6.
qbinom(.19, size=30, prob=.6)
I saw told that it some way it must return the inverse of binomial distribution, right? But tbh I don't see a connection there... Like, what does pth percentile has to do with the inverse?
If someone could provide some examples, that'd be awesome
@blissful condor, you may be interested in this 🙂
(please, let me know if you don't want to be pinged anymore; just thought statistics questions are of interest to you)
it’s okay, i am not a statshead but feel free to ping me. if you find anything that you think is interesting but not like a homework question, you can put it in #probability-statistics and people who are better at statistics than i am can comment on it and give good insight
I'll probably get bullied there tho, since I don't have the foundation in stats yet 😦
anyway
you won’t get bullied for having no foundation, hopefully you don’t get that impression, we are all just here to talk about math and how much we like it
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I'm reading about orthogonal projections and inner products, specifically in regards to least squares approximation, and suddenly I'm encountering this formula; $$\left\lVert u-v\right\rVert ^2=\left\lVert u\right\rVert ^2-\left\lVert v\right\rVert ^2.$$ Is this simply Pythagoras theorem? I know how to prove with a plus sign, but I don't know how to derive it when there's a minus sign. Any ideas?
Philip
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withou math jargon can any1 tell me what does interpolation mean
i cant undertsnad
it just means to estimate something
like find the value of something good enough for what ur working with
so what does extrapolate mean compared to that
it's like taking the data u have to guess about data you don't hvae
interpolation is usually referring to guess about something within the bounds of ur data
extrapolation is that same idea but for a value outside of ur range of data that you have
aproxing shape of curve?
hmmmmmmmmmmmm
well
i think in a sense, you could do something like that
but interpolate and extrapolate usually are terms used in stats when talking about trends and patterns and stuff
so say a line of best fit would be extrapolating?
yeah
I'd aruge it's both
tbh
argue*
ok got u, is hroner method /synthetic divion can also be done by dividing polynomial with all non real rooots
@bold badge
last ques
plz
I'm not sure so I can't say
oh ohk np
I haven't done polynomial divinsion since MS
and I'm now a junior in college sooo
lol
ohh i see , nw , i will close her and ask sepratly , will get reply easily there
thanks
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Consider the points A = (10, 4, −1), B = (12, 5, −3) and C = (6, 5, 9) and let L be the line through the points
A and B. Calculate the coordinates of the point P on the line L so that the triangle P CB becomes right-angled with angle π/2 at point P.
right angled means dot product = 0, that probably helps
Yeah i had a suspicion that was the case
however
This is what i think it should be like
I calculated the vector between the two points AB = L = B - A
But i need a vector from P to C and we don't know P?
So i'm not sure what to do
if P is on the line L
then P is like (10 + x, 4 + x, -1 + x) or something
probably with more coefficients
How did you come to that conclusion?
L: (10, 4, -1) + t( 2, 1, -2) @barren hound Is this what you mean?
yeah
so if you've got a point P on L then you know that P can be described by (10 + 2t, 4 + t, -1 - 2t)
and then you can just figure out what t is so that PCB is right angled
(x, y, z) = (5, 8, 11) + t(3, 14, 12)
With this equation no matter the t it will always be on the line however
@barren hound
i don't understand what those numbers are coming frmo
Yeah
so P = (10 + 2t, ... )
what about the condition that it has to be pi/2 ?
@verbal steppe Has your question been resolved?
@barren hound 
hi yes this is what i mean
so now you have PC and you have PB
or you can get PB at least
and you know that if angle CPB is a right angle then those two have a dot product of 0
So we take the vector PC and PB and the dot product of those should be = 0?
so PB = B - P = (12-x, 5-y, -3-z)
What now?

What's wrong? You have PB and PC so do their dot product
Yeah, now solve for x,y,z
x = 12 and 6
y = 5
z = -3 and 9
(12-x)(6-x) + (5-y)(5-y) + (-3-z)(9-z) = 0
Yes, now there's one more thing you know about x,y,z
(12-(10+2t))(6-(10+2t)) + (5-(4+t))(5-(4+t)) + (-3-(-1-2t))(9-(-1-2t)) = 0
(12-10-2t)(6-10-2t) + (5-4-t)(5-4-t) + (-3+1+2t)(9+1+2t) = 0
(2-2t)(-4-2t) + (1-t)(1-t) + (-2+2t)(10+2t) = 0
Continue
yeah i'm doing it on paper getting rough
One sec 
i got t to be 1, -3
,w (12-(10+2t))(6-(10+2t)) + (5-(4+t))(5-(4+t)) + (-3-(-1-2t))(9-(-1-2t)) = 0

Yes, though usually when you get two solutions one is degenerate
if t = 1 i get that P = B
Right
So it has to be -3?
To have a triangle PBC, yes
That makes sense because otherwise we dont get the triangle, only a straight line
Let me insert -3 and see what i get
P = (4,1,5)
You can use Pythagoras if you want to confirm that this makes a right triangle
I'm aware on how pythagoras works but i'm not sure how to apply it in this context
Or rather apply Pythagoras on points in a 3d envir
Pythagoras only deals with distances, it doesn't matter how many dimensions you work with
By distances I mean triangle side lengths
Yeah
So i use Pythagoras to calculate the length of each side of the triangle and then utilize trigonometry to see if they create a pi/2 angle?
Is this Pythagoras?
... is that not how you calculate the length of each side?
Yes
So what do you use Pythagoras for
To find the length of each side in a triangle
You just said this is how you do that, and that it's not Pythagoras
a^2+b^2 = c^2
okay i'm very sleep
Forget what i just said
If lhs = rhs = a pi/2 exists
:)
🙂
Ok that's not trigonometry though, no need to say pi/2 or whatever
If a^2+b^2 = c^2 then the triangle with sides a,b,c is a right triangle
Yes
I just completely forgot about that and thought that Pythagoras was used for only calculating the length of a side in a triangle
Ok so you actually use Pythagoras multiple times
Once for the triangle at the end, but also this is actually Pythagoras
(or a generalization)
Aah that makes sense
FYI, in software, when you want to know if a 2D point (x,y) is inside a circle with center (z,w) and radius r, you just do (x-z)^2 + (y-w)^2 < r^2
Similarly for a 3D point inside a sphere, there's just one more term on the left
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Integration by parts
@tranquil pine Has your question been resolved?
ok yea thanks
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can someone please help me with c?
take a look at subquestion a again
🤔
it's given that a + b is itself a root
right
but how can I use that
oh wait
A/2 is a root?
so I sub it back into the original equation
try it out :)
ok so far im on -A^3 + 24A = 0
-A(A^2 - 24) = 0
so A^2 = 24
so A = 2sqrt(6)
does that track
ok that's correct but i'd just like to let you know that that's technically not the only possible value of A in our case
yes
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hey i have a controls problem, im not sure if you'll be able to help but all i need to do is lable this correctly and im having trouble
there are a couple that i'm pretty sure are correct like signal 1 is the reference speed
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no it hasnt......
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,rotate
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Find dA/dt, but I'm using the formula A=1/4πD^2
sounds good
But I get 157
so what did you get for dA/dt?
is it multiple choice?
Yeah
!original
Please show the original problem, exactly as it was stated to you, with the entire original context. A picture or screenshot is best. If the original problem is not in English, then post it anyway! The additional context might still be helpful. Do your best to provide a translation.
oh i see your problem, dD/dt is given in terms of inches \ minute, while the width of the patch is given in feet
Ohh
so you'll need to convert the 20 feet to inches
Oh ok ok
since answers are in inches
Thank you
other than that, your logic is sound
Alright, thank you bro!
careful with those units, theyll get you on the AP test 😄
I know, I'm nervous about that exam
well you seem to be getting things fine
just remind yourself to double check when the problem involves units, it isnt that many of them
Truee, luckily
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I need help.
well fractions
so basically
u gotta find felles nevner
im from Norway
And im struggling with it
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how is x^5y^2 a potential
if you take the gradient of x⁵y² it gives you the given vector field
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✅
@formal trail I dont get it do i need to compute the partial derivatieves f(x,y,z)?
also i dont know how to do it with this intergral with dx and dy
normally i just got this to deal with
how do i get the vector field out of that intergral?
ooh
wait
nvm
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@formal trail one last thing. How can i see that the vector field is conservative
how can i see that this vector field is conservative
a vector field is conservative if a potential function exists (i.e. $f$ exists such that $\grad f = \vb{F}$. you can alternatively use the fact that $\curl (\grad f) = \vb{0}$ since that means $\vb{F}$ is conservative if $\curl \vb{F} = \vb{0}$
cloud
if you don't know that yet, you can also just try and find a potential function and see if it works or not
yes
gradient is an operator that takes a scalar function and returns a vector field. so F is the vector field you already have, and f is a potential function of F if $\grad f = \vb{F}$
cloud
@formal trail my gradiant is 20x^3y^2 +2x^5
gradient of what?
of this
you can't take the gradient of a vector field
you're trying to find a potential function f whose gradient is the vector field you already have
oh but how would i want to proof it would be conservative then by doing this
you need to find a potential function f, and take the gradient of f, and if that gradient is your original vector field F, then F is conservative
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Is this logic correct
,rotate
are you integrating $\frac{6}{x^2}$ or $-\frac{6}{x^2}$
ℝαμΩℕωⅤ
then yes
missing the dx
If I added dx, would it be good?
application of power rule is fine
What about when I move x to bottom
don't forget the constant of integration
+C?
that's the application of the negative exponent law, which you also applied at the start, is also fine
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pls
ty
Ms. Kitts works at a music store. Last week she sold 6 more than 3 times the number of CDs that she sold this week. Ms. Kitts sold a total of 110 CDs over the 2 weeks. Create a system of equations that can be used to find the number of CDs she sold last week, and the number of CDs she sold this week. Then use your equations to solve for each.
Can someone help help me solve this using linar systems its been a minute and this is my practice question totaly forgotten how it worka
works
What have you done so far
So you absolutely can not remember anything?
well i can start the question
How would you?
she sold total of 110 cds
Yes
idk bro
Okay
lowkey
So let the no of CDs she sold this week be x
lemme get my calc
They say she sold 6 MORE than 3 TIMEs the no of (CDs she sold this week)
Need not my brother
What do you infer from this? Can you make a relation?
6 x 6 x 6?
alr
Say John had y apples
ok
Laurence had 3 more than 2 times the no of apples than John
How many apples does Laurence have?
pretty please
I'm supposed to help you get the answer and not give answers
You're here to learn bro
😭
You could try
John has y apples so according to this statement, Laurence had 3+2y apples, does that make sense
not really
If Laurence had 3 MORE than 2 TIMES the no of apples than John
Laurence should have 2y+3 apples
Or 3+2y
Same thing
@supple atlas is this from khan academy algebra 1?
I was helping you to make equations
this guy has 2 apples
aint the formula
i want to kknow how to do it
not make the question
😭
Ok tell me this, you understood how to frame relations now right?
You understand the above examples right?
They're not related to your question at all they were just to help you frame relations
ok so for my question where do i start
May I also provide an explanation?
Ms. Kitts works at a music store. Last week she sold 6 more than 3 times the number of CDs that she sold this week. Ms. Kitts sold a total of 110 CDs over the 2 weeks. Create a system of equations that can be used to find the number of CDs she sold last week, and the number of CDs she sold this week. Then use your equations to solve for each.
please
Assume Mrs Kitts sold x CDs this week
yes
So according to the question, she sold 6 MORE than 3 TIMES the number of CDs than THIS WEEK
Let y be number of CDs sold last week
Then equate y=3x+6
And total CDs sold in both weeks add upto 110
okok
Basically the question is teaching you the method of substitution of solving linear equations in 2 variables
You substituted the value of y from one relation in the other relation
It's important to know how to form relations
Always remember a correct question will always have two meaningful relations to solve 2 variables
can you show me how its written i have the question and all that but in the formula i don’t understand substitution
See what does substitution here mean?
It means we are using the obtained value of y (from one equation in terms of x) in another equation involving both x and y
Are you following?
@supple atlas Has your question been resolved?
sorry bro thanks
who can help
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Last 2 times my ticket got cloed without an answer so lets try this again...
But can someone explain each of the different types of angles and how they relate (not just ones in here but all types I would find) and bow they relate?
i want to know the anme all of types of angles that can be related and like how you can get there degress based on that other one its releted to
unless you have parallel lines, these angles generally don't relate to each other at all
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is there specific names for them though? in my assignment im suppost to and i remeber there being like 5 dif names or something like that
corresponding will be on the same side of the transversal
so 1 and 3 are transverse in Q6, for example
eh, let me find something
okay 1 sec i may have another question about this so dont close the chat
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how do i use polar coordinates here?
Transform x and y to their r and theta formulas
should i intergrate theta first or r?
and can i factor them out of the intergral of r?
Depends on D
You're missing dA
can you give me a hint how to proceed further? @vital crag
okay but besides that
And you're missing your limits in theta and r
Just do it
Don't even know what you're asking for
.
how long are you online @vital crag ?
Stop pinging me
@vital crag im stuck
.
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hey could someone help with this problem please
<@&286206848099549185>
What have you tried
i think that if 2 vectors arent parallel they span a plane, i think these 2 are right
If 2 vectors aren’t parallel then yes they span a plane
But what’s that got to do with this question?
Let’s start with the first one
How can you know if x lies in the plane spanned by u and v?
is it that each on of the numbers in the x vector are between the same numbers on u and v?
What do you mean by that
the first number in the x vector (1) is between or equal to the first numbers of the u and v vectors (0 and 1)
and each of the numbers fit, so i would guess that the first one is correct?
I see what you mean, but this type of reasoning would be easier if you wrote x as a linear combination of v and w already
You've very much almost found it, just need to formalize it
im not sure what you mean, i looked through the question and found every thing to be true which i dont think is right aswell
Well it's impossible for all of them to be true
Since u and v are not colinear, they span a plane
If u,v and w together spanned a plane
Then w is immediately in the plane spanned by u and v
So it's a linear combination of u and v
So answers 3 and 5 are already incompatible...
mm ok. so i think 3 is wrong 5 is right
Just remember
"c is in the plane spanned by a and b" exactly means "c is a linear combination of a and b"
(Meaning c = xa + yb)
So let's check answer 4
so what i said earlier was wrong, it doesnt mean that the numbers are in between?
The justification is not completely valid no
There is a step in between
And that is showing that x = av + bw
So, if a and b exist, what are they?
uhhh
Focus on the 2nd and 3rd coordinates
not sure
Your remark that x's coordinates were "in between" those of v's and w's was practically on the spot...
But "in between" as in what more precisely?
1/2?
is a and b both 1/2?
it does
It does what?
the equation works
i mean
is there something else im suppose to conclude?
that they are a linear combination?
.
Pretty much if you wanna be sure.
If a and b don’t exist, then x cannot be in the plane spanned by such and such
also if 3 is right does that mean 2 is right? or are they different things?
Yes
ok
If w is in the plane of u and v, then u,v and w make a plane
so i unchecked the first one, and have the 3 middle ones checked, you think thats right?
x is indeed not spanned by u and v
Because if x = au + bv, we would need a = 1/2 and b = 1, which doesn't work...
So 1 is wrong
For 2 I suggest you try the same thing
Find a and b such that w = au + bv
i dont think it works
Aye so if no a and b exist, what can we say?
its wrong
so i was wrong to say this?
they are different things
No, what you said here was right.
3 and 2 are indeed equivalent statements
but we found 3 to be correct but 2 to be incorrect?
When did we say 3 was correct?
yes? or is 3 wrong since 2 is
We said 2 and 3 were equivalent
Sounds good to me
alright thank you
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FOIL
Foil Formula is the steps used to find the multiplication of two binomials while using the distributive property. Understand the foil formula using solved examples.
Oh i learn about that
but how do i do foil
there’s only 1 of them
1 polynomial
x^2 = x * x
@normal jasper Has your question been resolved?
Oh
dr. matlab plot
Follow this
.
@normal jasper Has your question been resolved?
@normal jasper Has your question been resolved?
woods
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I got this wrong and want to know where I got off track my teacher said formulas and everything is correct
