#help-10
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@timid silo Has your question been resolved?
It's correct intuition. Maybe just make it clear that you pick (x,y,z) in S and all but that's it.
@timid silo Has your question been resolved?
iirc any plane through the origin is a subspace of $\mathbb{R}^3$
Katharine
similarly any line and the origin itself are subspaces too
although i don't think that will help you if you need to prove it by showing it fulfils the properties of a vector space
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do we take the value of PQ = 1 as ([1,0],[0,1]) because i do not know how to approach this question
It is an I (for identity matrix) and yeah it is that matrix
so i'm etting the answer as a = 4 and b = 1
is my answer right?
i first mulitplied the P and Q matrices and got ([a-3, -a+4],[3-3b,-4+4b])
which is equal to I
so then a - 3 = 1
therefore a = 4
and 3b - 3 = 0
oh wait 3-3b = 0
3b = 3
b = 1
Yeah that is correct
np
The two matrices have to be inverses so you can check quickly by taking the inverse of one of the matrices and see if you get the other matrix
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i dont know how to do part b
@burnt otter Has your question been resolved?
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How do I sketch the set of points (x, y) in the plane corresponding to the inequality?
yeah so
what I got is a hyperbola with center at (1,1)
like this
and then a restriction y <= 1 and y cannot be y = -x + 3..
and idk where to go from there
thats all
wdym?
its (probably, didnt check your calculations) the hyperbola you found with the restrictions y>x, y>-x+2
then the area above the hyperbola in that region (honestly or below idk try plugging in 1 point to see if the hyperbola is positive or negative
so like how would u sketch the solution?
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How to write this as piecewise function?
piecewise function i assume you mean?
start with if x > 0
The root inside the absolute value is zero, but it is not defined when it is in the denominator
What I learned in school is that we get the root of the absolute value and put X greater than the root and smaller than the root and write the formula in this way. But the question is that the root is not defined here, so what should we write next?
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Please explain.
What is that??
what is what
k || l means that lines k and l are parallel
and the one under that
perpendicular
How it will look like on the graph
you need to read in your school book about the geometric interpretation of solutions to a system of linear equations
so leave it
like that r smthn
No, I need to know how it works, I have an exam tomorrow
ah ok 🙂
And these kinds of equations will be in the exam mostly
Strange
its a st. Line
Parabola is a curve
perpendicular lines are 2 lines that form a 90° angle at their point of intersection
Alright then, just tell me how they make these formulas
For parallel lines, the gradients of both lines must be equal
For perpendicular lines, the gradients of both lines should multiply together to get -1
gradient = slope
Rise over run, change in y divided by change in x
?? 😭😭
👆
What?
for example a straight line forms on it, it has a gradient of 1
now we substitute y=mx+c, assume c =0
y=1x
m is a gradient?
if x is 1, y is 1, it forms as a point on the gradient/slope, obeys the same with anypoint in the curve
yea
and c is like if you move the slope/gradient up or not
yo bro now I get it
In that case at the top, it is “a”gradient
or “a” and “b”?
a and b is a point forms on the line
or we call it coordinates
it obeys slope formula y=mx+c
Alright, gradient it is the distance between two points, for instance, A(-3;6) and B(5;9) if we do y2-y1/x2-x1 we find the distance, or a gap between these two points?
and it will be like a line
slope means hypotenuse?
yea you can call it hypotenuse
to classify slope is a straight line with a certain formula , like 3/8 as mentioned above, and points forms according to the rule y = mx+c, but hypotenuse is the distance between each point, where we can use pyth theorm to find it
in this case find their slope
which is infinity cause they just extends
if slope of ab = cd then yes
And how will look like perpendicular one?
Oh this is perpendicular
no thats just the gradient of a line
Why m1m2=-1?
its the case if it’s perpendicular
What if parallels
But why in that equation it is said that a1a2+b1b2=0 and they did not use m1m2=-1?
rearranged it is
by=c-ax
And yp get it in y=mx+c
u divide through by b
so ur gradient is -a/b
then u do some trickery w that and u get what u need
ahahha trickery
Idk u shld start studying before its ur exam
instead of cramming it in the day before
I was busy
I completed gta vice city for 100%
🤩🤩
@timid silo
yes
I think that is enough for this equation, but hehehehe there a lot more questions about other equations, especially parabolas, I hate parabolas
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On a segment AB = 2a, taken as a base, three isosceles triangles ACB, AC'B and AC"B are constructed, with respective heights a, 2a and 3a. Prove that C + C' + C" = 180º.
Draw the figure
it's here.
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what did you do?
I calculated with Pythagoras the length of BC, BC' and BC''. And after I use the sin and cosine functions to calculate the angles using Arcsin and Arcos, but I obtain something like 340º.
actually trig isn't necessary, do you know about similar triangles?
(also, you should have probably used arctan)
Thales.
Yes. I try with all trigonomety functions.
Can you prove that CC'B and CBC'' are similar
How?
C stays in place, C' maps to B and B maps to C''
Ah, it is like rotating the triangles.
What is sas?
side-angle-side
Ok, thank's for help. I will try again.
@low dune Has your question been resolved?
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Please someone explain.
I don’t really understand what does E and D mean and how to solve such kinds of equation. I also don’t know what is “y.max and (x^2+2).min. This is an example.
It would be great if you explain what they have done step by step.
<@&286206848099549185>
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.
@keen rune Has your question been resolved?
In this case it looks like e and d are just the function symbols
like the f in f of x
y max is the maximum value of your curve on the y axis
E and D ?
yeah sorry
and the min = 2 is essentially telling that the function x^2+2 has a minimum value of 2
on the y axis
Why y>0?
How they found out
If I face such kinds of equation I wanna know how to spot that y>0 or y<0
basically you can see it's all above y axis
it never touches y =0 or goes beneath it
so it always >
Yes I can see from that graph, but how to draw that?
wdym?
How he drew that graph
yea when you put (0,2] you’re saying 0<y ≤2
oh
I drew that by inputting the formula into desmos’
Hahahaha
so what they did
is that they extracted potential restrictions on x
so they solved for x^2+2 which is the denominator
with a y minimum value of 2
when x=0
and the maximum value for 4/(x+2) is 2 when x=0
is not it 2
yes sorry 2
ok, we should put x=0 and look for the max and the min?
And after we found them, what then?
no it depends what kind of equation you have but in this equation it works since you have no horizontal displacement
How it will look like when it is to the left?
that is to the left
and the minimum value for y in this case is at x=-2 y=2
(-2,2)
have you learnt polynomials and ax^2+bx+c
you can use the -b/2a formula to find the vertex
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yeah... not 'clearly' to me lol can someone explain how they got that last sum
there's more context to the problem obvi but im just specifically asking about that last step
the coefficient thing
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help
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what topics would I need to know to solve this, I don't want a solution , just want to kow what I need to know to solve this. Thanks ! source:_ jee advance 2023
S=70+700+7000+70000.....+5+55+555+5555+55555......+2+2+2+2......
so it's elementary factorisation of sorts ?
Geometric series
not exactly a gp
Well you would write is as sum of geometric series
thanks ! Also, profile picture checks out, given how fast you solved it.
sorry if that's insulting
thats actually a compliment
also note that you must very carefully determine number of terms of each of the three series
aren't they all 98?
no
ok, that's enough of a hint, I'll figure out where I'm going wrong from here. Thanks so much!
welcome 
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Need help with 10(10)
what have you tried?
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Can anyone help in this prob
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i did this
i think i proved that if a_n is absolutely convergent then a_n+ and a_n- both converges
but
if a_n is conditionally convergent which means that a_n is convergent and |a_n| is not then i am getting that a_n- is convergent by comparison test
where is my mistake?
yes this is right
if |an| converges it implies an+ converges and an- converges
what about (b)
what is b?
b question
here (b) question
?
no they are different
ok if an is conditionally convergent, it means the series |an| converges but the series an itself diverges
ni
it is completely opposite
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is there a way to graph trig transformations using the 5-point method IF there is a restriction?
I find it's taking longer + more resources to figure out where the graph ends with the 5-point method
versus just using a table of transformations
https://www.youtube.com/watch?v=Vw-RwPBWS8g << Is what I'm referring to with 5 pt method
This trigonometry and precalculus video tutorial shows you how to graph trigonometric functions such as sine and cosine functions using transformations, phase shifts, period, and amplitude.
Verifying Trigonometric Identities: https://www.youtube.com/watch?v=Rf05H8ogHLg
Sum and Difference Identities: ...
@timid silo Has your question been resolved?
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Hi can somebody please explain what this expansion is?
Just binomial theorem
it looks, it is being played with Poisson distribution here
[(x+y)^n = \slm{k=0}n\binom nk x^ky^{n-k}]
Pure

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Hi, how would I solve this step by step
So I move everything to the other side
U need to realizify the denominator
By multiplying the denominator and numerator by the conjugate of the denominator
Then split Complex(z) into Re(z) +i*Im(z)
.
When u divide both sides by 3+7i
First this then multiply nom and denom by the conjugatw
Conjugate of what
3+7i?
Yes
@languid fern Has your question been resolved?
Done thanks
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There are two fixed points on a triangle - A and B above the x-axis. Where do you position the third point, C on the x-axis such that the angle ACB is the largest possible.
Please don't occupy multiple help channels.
Consider a circle passing through points A and B. To maximize the angle ACB, we want the line segment AB to be the diameter of the circle
What
But
That doesn't always work
Because C has to be on the x-axis
<@&286206848099549185>
Can I use trig in any way?
@muted delta Has your question been resolved?
<@&286206848099549185>
@muted delta Has your question been resolved?
@muted delta Has your question been resolved?
well, logically, C would be right in the middle of A and B with its y-coord = 0
not sure how i'd do it with algebra or trig tho
actually, forget that too. it doesnt seem to work when A and B both have the same x, but different y
Nope
That's not true
They can't have same x
i think if you reflect one of the points across the axis and then connect them with a straight line you get your answer
that one minimizes distance at least
take one of the points and reflect it across the x axis
then connect that new point to the other one yeah
Lemme try this
I don't think thats it
hmm
Sure
i feel like you'll get a very simple answer out
I should
I hope
What could I do with this
I don't know very advanced calc
I tried using inverse tan but it becomes too complex
idk if this will work, but you can try it this way:
make a circle passing through A and B, and has x-axis as its tangent.
wherever the circle touches the x-axis, is C
But where is that
It's funny that was my original problem
And I made it into this
@me if you got ideas, cant figure out
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2. I have begun but got stuck midway.
3. I got an answer but I was told that it's wrong.
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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
Hint: notice that the numbers $\frac{-1+\sqrt{-3}}{2}$ and $\frac{-1-\sqrt{-3}}{2}$ are the roots of a quadratic equation
ItzKraken
that, or notice they are cube roots of unity.
Ah yes that's perhaps easier
Well use that property
U can write it as $(\left(\frac{-1+\sqrt{-3}}{2}\right)^{48})^2$
ItzKraken
Oof i wrote it wrong
That'd be the both of you.
But well w^50 = w^48 * w^2
that's not omega^1/3 but OMEGA.
did you actually mean this
or not
You need the sum mentioned in the question.
Let it be omega^2
And start simplifying the other term.
The other one isn't omega^2 though?
Is that your sum?
Yeah that's wrong.
Well not quite
If $\f{1+\sqrt{-3}}{2} = \omega$ then $\f{1-\sqrt{-3}}{2} = \omega^2$
! What the hell am I doing here?
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I was having trouble calculating how much stretch foil do I need to wrap a single pallet, here are the basic pallet and stretch foil info:
Pallet dimensions:
H: 2.4m
W: 0.94m
L: 1.34m
Foil:
L: 1300m
W: 0.5m
Pallet would be wrapped 3 times
Yes
Yes, 3 layers, but every layer goes over the half of the previous one, to make it more firm
But 3 full stretches in total
@graceful iris Has your question been resolved?
not sure i understand this
i'd need to see some kind of diagram
but like the way i see it rn you're covering a box with 3 layers
so just find its surface area and multiply that by 3?
I explained it poorly, since the foil width is 50cm whenever a layer is laid the next one is put over the bottom half of the previous one, until the full pallet is stretched
im gonna need some kind of visual here.
Okay hang on
Every layer goes around the whole pallet, but also over the previous layer, at least 50% of it, so it holds better, until the whole thing is stretched with foil, 3 times
so you keep going until the SIDES are covered in 3 layers of foil
and you don't do the top and bottom
right?
(also this looks like clingwrap and not foil)
Stretch film, not foil correct
The top is also covered
Bottom same as in the picture
Correct
ok but wait
then you also put the thing on its side and do the same 3 layers stuff right
So you go around the pallet like the picture, covering it gradually from bottom to top
Bottom like this
Top is not covered fully, just the edges
sorry, i am confused.
ok, so the face that touches the floor is not covered.
and neither is the top.
the area of the other four faces is 2HW + 2HL
so you need 3 times that
Correct
No it's fine, I explained the whole thing terribly
@graceful iris Has your question been resolved?
ok so what is troubling you now?
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i have a conjecture
suppose you have two integers- (a, b)
the conjecture is that
for some (x, y) belonging to Z
ok nvm i got it
ty ig lmao
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Solve the equation
You can just do
1x^2 + 3x + 7
you get two x values
And then how do i turn it back?
e^x = value 1 e^x = value 2
?
firstly not an equation
secondly don't use the same variable to represent different things
if you want to make a substitution to get a quadratic equation, use something that isn't x
ah ok
I understand what you meant now
A = e^x
A^2 -5A +4
A = 4 and 1
e^x = 4 e^x =1
and then from there.. right?
from that find x?
yes
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@fossil turtle Has your question been resolved?
a good way to imagine it is by "unfolding" the pool tabke
instead of visualising the ball is bouncing back and reflecting
imagine it keeps continuing
so it first goes up by 3 units
then you imagine it doesnt bounce back/reflect
and it keeps going up 4 more units, outside the table
and then lastly it goes up 2 more units
so in total it went up by9 units
or delta y = 9
and horizontally it travelled 4 components
so delta x= 4
and slope = delta y/delta x
so the slope of the initial line is 9/4
and you should be able to work from there
@fossil turtle
Thank you
<3
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A device is designed in such a way that by chance it takes one of the two letters A or B from the input and after going through three stages
Prints 1 character in the output. In each step, the input letter goes to the next step with a probability of 1/4 without changing, or it changes into another letter and enters the next step. If the probability of choosing the letter A is 2 times that of the letter B, with what probability is the letter A printed by the machine the same as the input letter?
Ok guys you didn't solve the previous one. Don't let me down on this one
@timid silo Has your question been resolved?
Nope. It has not
<@&286206848099549185>
<@&286206848099549185>
<@&286206848099549185>
Bruh how long must I wait?
Helpers are just people volunteering their time to help you. Be polite and patient.
its christmas, u cant expect everyone to be on here
Oh that's a good point
when it “changes to another letter” can that letter be any letter in the alphabet or is it limited to just A and B?
@timid silo Has your question been resolved?
No just A and B
Im guessing the last part saying A is double as likely as B is only referring to the first part?
the initial selection
And are we only calculating the probability of the input and output being A?
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hi guys, how do you prove rigorously that {(-1)^n, n∈N} doesn't have accumulation points?
i'ts easy to see that E={1, -1, 1, -1, ...} but how do you prove it rigorously?
consider two subsequences: n = 2k and n = 2k - 1, that is all
did you mean this as a sequence?
or as a subset of R?
bc as a subset of R this is just {-1, 1} is it not?
yes
and you're meant to prove that this sequence doesn't have accumulation points at all?
and your question had been set wronglty troo
why do -1 and 1 not count as accumulation points for you? @celest musk
your sequence has two different accumulation points and is therefore divergent
the question was not (or at least did not seem to be) about convergence or lack thereof.
because if you choose a small neighborhood like 1/2, then 1-1/2 = 1/2 is not an element of E
same for -1
hold on
hold on, hold on.
that doesn't seem to mesh with any kind of definition of "accumulation point" that i know...
do you have one on hand? y/n
i haven't studied those things yet, just topology of the real line, surroundings and accumulation points
ah.
ok, right.
so we're considering {(-1)^n : n ∈ N} as a set after all.
so it is just the finite set {-1, 1} of two points.
and it does indeed not have any accumulation points.
and neither does any finite set.
yeah
every point of a finite set is an isolated point.
you confused us earlier bc i thought you were talking about the sequence (-1)^n, which has 1 and -1 as limit points / points arising as the limit of a subsequence
ok so how do you prove this using the definition of neighborhood?
let $E \subseteq \bR$ be finite, let $x_0 \in E$, and let $E_1 = E \setminus { x_0 }$ (for convenience). we wish to show that $x_0$ is not an accumulation point of $E$, i.e. we wish to show that $$\exists \ep > 0 : B(x_0, \ep) \cap E_1 = \varnothing.$$ do you follow so far?
Ann
@celest musk
yes
Ann
as long as you have access to the following facts:
- the minimum of a finite set is a thing that exists
- the minimum of a function over a finite set is also a thing that exists
- the minimum of finitely many positive numbers is itself positive
- half of a positive number is still positive
sorry i don't understand this
as in you can't read it?
yeah
compute the distance from x_0 to all points in E_1
(i.e. to all other points of E except x_0 itself)
take the smallest of them
and divide it by 2
can you give me an example please?
where x_0 is 1 or -1
these things are hard for me not trivial lol
i will need you to type the exact words "Yes, I want you to do it for E = {-1, 1}" before proceeding. otherwise i will not do it
Yes, I want you to do it for E = {-1, 1}
please
Ann
the minimum distance from x_0 to a point in E_1 is the distance from x to the ONLY point in E_1.
and so this is 2
and so the epsilon given by my proof would be 1.
Tommy, your proof is that if you take any real number x other than -1 and not 1, then if you surround "x" with a ball = surroundings of any sufficiently small radius epsilon, then you will not find either -1 or 1 in that ball
and Ann has shown it for you
@celest musk Has your question been resolved?
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✅
took me a while but i think i got it, thank you very much
okay got it thank you very much
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!help
To ask for mathematics help on this server, please open your own help channel or help thread. See #❓how-to-get-help for instructions.
This problem is pretty much proof by construction unfortunately.
Note tho that
[\wrb{(n+1)^3+(n-1)^3 = 2n^3+6n}]
Maybe you can go from here
snow
Every integer divisible by 3 can be expressed as 6n or 6n+3
What do you mean by proof by construction
read here, no need to copy it and paste in discord 🙂 https://en.wikipedia.org/wiki/Sum_of_four_cubes_problem
The sum of four cubes problem asks whether every integer is the sum of four cubes of integers. It is conjectured the answer is affirmative, but this conjecture has been neither proved nor disproved. Some of the cubes may be negative numbers, in contrast to Waring's problem on sums of cubes, where they are required to be positive.
The substituti...
If you want to try the problem yourself, try adding two more cubes here so that you get 6n.
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Animals at a zoo are assigned into many different groups. Each group must have at least two animals, and every group shares at least one animal with every other group. Prove that you can split partition animals into exactly three "splits" such that each group is represented in at least two splits, and each animal is in exactly one split.
@muted delta Has your question been resolved?
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@muted delta Maybe you should post this in MODS, because this seems like an olympiad problem
mods?
Math olympiad discord server
https://discord.com/channels/533153217119387658/533157665430568981 this channel probably
i probably don't understand the rules, so there's like a venn diagram and a bunch of animals
and we need to color all animals in 3 colors
you can just use 2 colors however you want, and then use 3rd color for one animal in the middle
then each group will automatically have 2+ colors in it
weird question
@muted delta Has your question been resolved?
Yes
well no
Because they can be arranged in any way
we're guaranteed 1+ animal in the middle
by reserving one color for one of middle animals, we solve the problem
yeah but that’s only for the three groups case
this is not general
Given a specific set it’s really easy to come up with it
How do you prove it in general is kinda hard
well it kinda says like there's an animal shared by every group, you think it means something else?
it could say "with some other group"
but it says with every other group
It means that
Every group shares at least one animal with every other group
So let’s say the groups were A, B, and C
You know that A and B share at least one, B and C share at least one, and A and C share at least one
But that doesn’t imply all of them share one
maybe
I’m pretty sure we have to make an algorithm
That sorts the animals from the groups into splits
and show that when it ends
You have the right arrangement in the splits
@muted delta Has your question been resolved?
@muted delta Has your question been resolved?
Well the groups are predecided along with the animals
If you only had 2 animals you could have max 2 groups
Yeah do you could have two groups with 0
and they share two
0 by themselves
@muted delta Has your question been resolved?
Bro I waited for so long. I turned off the phone since no one was answering
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can someone help me with this question
Allen?
lol yea
alright
orthogonally means 90 degrees at vertex or focus?
u r also in allen ?
no I'm in 10th ehh
how do uk then?
olympiads
I think m = -1?
@twilit meteor
that's what you need to do ig
can u ans this
wdym by vertex / focus?
nvm
oh
how did u get that
yea
yes
oh k
tks i shall do it
i was only confused abt whether orthogonally meant subtending angle at vertex or smtg else
tq @stone radish
alr
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np
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In a singles tennis toumament, 2n players are paired off in n matches; an
denotes the number of different ways in which this pairing can be done.
!status
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
ill try
okay
so the total number of ways to choose a pair is
2n choose 2
how did u get that
ok
lets say you have 4 elements in a set
or 4 letters
A B C D
so A will form 3 pairs (n-1)
(AB, AC, AD)
B will form 2 pairs (n-2)
(BC, BD)
and C will form 1 pair (n-3)
(CD)
so in total
we just found out the combination
I was trying to do this with recursion
so total number of ways to choose k items from n items is nCk
yes i get that
Thank you!
@stone radish
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$\int f(ax+b) \dd{x} = \frac{1}{a} F(ax+b)$, where $F$ is a known antiderivative of $f$
Ann
you can also view it as a $u$-substitution: in $\int \cos(3x+1) \dd{x}$, take $u := 3x+1$ and it'll fall out
Ann
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how do you do this
Translate, please
a) Show that x_n >= 2 \forall \in \mathbb{N}.
b) Study the monotonicity of the sequence (x_n).
c) Study the convergence of the sequence (x_n) and determine its limit.
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anyone knows how to solve these?
do you know about Gaussian reduction
or simply known as solving systems of equations by elimination
give both x and y solutuions, specify which problem
yes
@torn river Has your question been resolved?
hmm ok wait
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I am doing some operations and at a certain moment I get this: 594!
And I put it in the calculator and I get infinity, but it doesn't make sense.
What comes out then?
are you doing combinatorics of some kind?
No, I'm doing Chudnovsky's formula for π
enlighten me?
Why?
i'd like to know what that formula is
Wait
but if you think it below you to enlighten lowly plebs like me then there's no need
The Chudnovsky algorithm is a fast method for calculating the digits of π, based on Ramanujan's π formulae. It was published by the Chudnovsky brothers in 1988.It was used in the world record calculations of 2.7 trillion digits of π in December 2009, 10 trillion digits in October 2011, 22.4 trillion digits in November 2016, 31.4 trillion digits ...
Quite boring
$[\frac{1}{\pi} = \frac{426880 \sqrt{10005}}{\sum_{n=0}^{\infty} \frac{(6n)!(3n)!(n!)!}{(3n)!^3 (n!)^3 640320^{3n+1/2}}}]$
H^Ψ(r)=EΨ(r)
Compile Error! Click the
reaction for more information.
(You may edit your message to recompile.)
@lyric mural Has your question been resolved?
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is the symbol for implication commonly used?
First time i see the notation of a set meant to denote implication
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Need help with this functional equation: f(x^2 + f(y)) = f(f(x)) + f(y^2) + 2f(xy)
I have gotten that f(0) = 0
f(x) = f(-x)
f(x^2) = f(f(x))
and f(x^2 + f(x)) = 4f(x^2)
@rocky pebble Has your question been resolved?
yes, the solution is f(x) = x^2 and f(x) = 0
but it has to be proven
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Havin trouble with part c
I got that 15a + 10b + 6c = 120 through manipulation
b should be greater than or equal to 12
and idrk where to proceed
it gives n(a/2+b/3+c/5) = n/30 * (15a+10b+6c), so I agree
But why b >= 12 ?
notice that c is divisible by 5 => c = 5k for int.k => 3a+2b+6k=24, here notice that b is divisible by 3 and etc.
after this you will get equation that is much more easy
cause wouldn't 10b = 120 - 15a + 6c
10b = 3(40 - 5a - 2c)
When a = 1 and c = 1 (minimum values i think)
10b = 3(33)
10b = 99
since b is divisible by
b is greater than or equal to 12
no
you've proved here that a=1, c=1 leads to no solution because 10b=99 has no solution
if you consider, say, a=2, b=4, c=10, that's a solution
it has b =4, not >= 12
but how can b = 4 if b is divisible by 3
b = 3z for some integer z > 0
3a + 2(3z) + 6k = 24
a + 2z + 2k = 8
a = 2m for some integer m > 0
3(2m) + 2z + 2k = 8
3m + z + k = 4
Have I made a mistake cause the last equation isnt working
😭
in pre-last line
it should be 2m+2z+2k=8
OH yeah
m + z + k = 4
ty
so for possible triples (m,z,k) are
(2, 1, 1)
(1, 2, 1)
(1, 1, 2)
Meaning possible triples (a,b,c) are
(4, 3, 5)
(2, 6, 5)
(2, 3, 10)
ty
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So I have done some math and I've come to:
wind (vector) = [-13.01, 1.94]
|wind| = 13.16 km/h ---> this is the speed of the wind which is the correct answer
θ = arctan (1.936/-13.01)
θ = -8.46 degrees
if i do add 270 degrees + 8.46 degrees i get a bearing of 278.46 degrees which is the correct answer
i dont understand why my θ is negative.
to solve for the wind vector I did (ground velocity - heading) after converting these two to cartesian vectors
arctan cannot differentiate between the second and fourth quadrants because it only sees the ratio of y to x, not their individual signs
