#help-17
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how would we do that?
since we want to find the area between two curves, we need to fins when they intersect
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consider something like 5x - 5x + 7
- this is an expresion
- no matter what value x has, the expression is 7
- so, this expression is the same for all values of x
are you with me so far
ohh
so 3(x+7)-(2x+9) = 3x + 21 - 2x - 9
?
3x + 21 - 2x - 9
3x - 2x + 21 - 9
x + 12
x + 12 changes for all values of x
1 + 12 is not the same thing as 2 + 12
so no, you did not successfully read the problem
this is a blank, you are supposed to put a number inside the blank
you have to put a number inside the blank so that something like this will happen
if you put nothing in the blank, it is incorrect
@vast shale to start, do you know why 5x - 5x + 7 always remains the same for all values of x?
hmm
because of constant 7?
because x is unknown and therefore it remains?
0
what is 0 times 100?
0
what is 0 times anything?
0
what is 0 times x?
0
so this reason doesnt wokr
x is unknown, but 0x is very much known, its always 0
it doesnt matter what x would be for 0x to be 0, right
yep
whats 5 * 7 - 5 * 7?
35-35 = 0
whats 5 * 100 - 5 * 100?
500-500 = 0
do you need to calculate 5 * 100 to see that 5 * 100 - 5 * 100 is 0?
you mean to do 5x - 5x = (5 - 5)x?
yea
uhuh
so 5x - 5x is always 0, right?
yeap
now lets look at this
you can put any number in this blank
but youre looking to put in a particular number
its a fraction
you need to put a fraction in this blank
so that the xes subtract each other out
just like they would with 5x - 5x
3x + 21 - ??? * (2x + 9)
do you have any ideas on what would work in that ???
so i need to form an equation?
cmon
3/2?
but how
is there like a systematic approach?
damn..
youre not going to memorize the solution to every problem out there
this is one of them
thats why its in the challenge problems
youll just need to figure out that its coming
did you tried AOPS books?
I dont use them, but if you need them thats up to you
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Can someone help me with this question like where did the underlined part come from? is it like multiplying x^2+1 to all values to cancel out the denominator?
Uhm in the available helps
But you are already asking for help in a question here, can I still ask mine over that?
Not really
Alright, I will find a empty one ig
hi
that multiplies fractions
remind, every number is always divided by 1
so ln(xx+1) is also = ln(xx+1)/1
then multiply extremes and middle
to get only one fraction
oh okay thanks
okay
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I'm very confused
here's my work:
sps the velocity of the airplane is u = <0,300>, and the velocity of the wind is v = <0,30>
a=u+v=<0,330>
a=330cos90i + 330sin90j
for the airplane should arrive at a point due west, the velocity must be <-330,0>
330cos(theta)=-330
arccos(-1)=180=theta
so now my answer is to head -90 degrees N?
which is just wrong tbh
okay update: i thought that maybe i should think of it as the plane has already moved towards west with a velocity of <-300,0> then the wind should be blowing it to it's side which produces a vector of the plane's velocity and the wind's getting added
now the plane have to adjust for that angle?
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It's wrong yeah, the last row times the first column doesn't give 0
Mb on the late edit haha
,w [[1,1,0],[1,1,1],[0,0,-1]]^-1
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np
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don't you have a theorem about alternating sums?
Oh
So we set $\frac{(k+1)}{2^{k+1}} = 10^{-3}$, right?
Kepe
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One more thing:
it has to be alternating
Well what if a_k < 0
Then it can alternate too?
so long as it's of constant sign
Hm, why does it say a_k >= 0 then
Probably a mistake
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how do i do this question? im confused af
and quotient obtained while dividing, does it mean i directly divide equation p(x)/g(x) like that?
i think option 3 is correct but i dont understand option 1 and 2
The limit of a polynomial is the limit of the dominant coefficient
So what would you get?
what is dominant coefficient?
so i need to transpose the value of x to infinity?
Did i say something wrong ?
i honestly have no idea
like consider the value of x as infinity?
if yes, then the whole equation will turn infinity
yes, dominant coef is not the correct terminology
What should i say, not a great english speaker, i translate litteraly
You sure?
how do i calculate turning points though? like i plot it on graph and see how many turns the graph will take?
leading term,
not coefficient as that only refers to the constant component
not really but like infinity raised to power something will still be infinity right?
i mean like at the end it will be infinity - 2
But it is -x^5
OH WAIT
-1(x^5)
Then, the first is true or false?
and both will cancel out
No
false
false
Ok yeah i see the mistake ty
Why
because both of them will lead to - infinity
Read again
instead of +infinity as it seems in the options
wait no
-x^5
option 1 will be false, 2 will be true
Exactly
I let u finish the other two by yourself
how do i calculate turning points?
and by option 4, i just divide p(x) by q (x)? @loud walrus
sorry for the ping
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Hi there, a short combinatorics/probability question. Should be around highschool level (Ive forgotten a lot):
How can I calculate the chance c that
play over r rounds
with l as chance to lose
that I will lose t times in a row at least x times?
My working till now was just setting t=3, x=1, r=200, l=0.3 just to test things. So for 3 rounds the chances are 0.3^3. For 4 rounds I have 2 possibilities of 0.3^3 occuring, so 0.3^3*2?
For 5 rounds it looks like it should be 0.3^3 * 3, which led me to believe that it should be (r-t+1)*l^t=c
This is obviously wrong, since it can exceed 1, although I expect a chance.
I hope the question is concise enough; can anyone nudge me in the right direction?
one of my problems is that all possible outcomes r^2 (since one can only win or lose) are not evenly distributed.
If anyone can help me to formulate the problem better (and with the right vocabulary) I am all ears!
<@&286206848099549185> anyone any idea?
@humble surge Has your question been resolved?
<@&286206848099549185> Does my question need reformulation?
@humble surge Has your question been resolved?
clarification: the loss-streaks can overlap. the chance to win/lose each round are independent of each other
Probably I misjudged the difficulty of the problem, might this be university level?
I think your formula is missing (1 -l)^(r-t) for the rounds where you win
Im not sure I follow; why would I care about the rounds where I win?
I thought I need to find all combinations there are (1). Then find all combinations with at least t losses in a row (2). Then calculate the chance of these rounds (3). Add all the chances up (4). That would be the plan, but I fail to see how to express it mathematically
@humble surge Has your question been resolved?
Consider these values
t = 3, x = 1, r = 5, l = 0.3
There are 3 scenarios where we lose 3 in a row:
'+' win
'-' loss
In the first scenario, we encounter 3 losses and then 2 wins
In the second scenario, it's one win, 3 losses, one win
For example, the probability of the second scenario occurring over 5 rounds is 0.7 x 0.3^3 x 0.7
In every scenario, there are 3 losses and 2 wins, all of which are independent of one another so the probability of one singular such scenario is always 0.7^2 x 0.3^3
We want to consider the probability of any of them occurring. Each one has the same probability so we can just multiply the probability of the number of scenarios. That is (r - t + 1) as you've noted
I realize you are likely aware of most of the stuff I mentioned later in this message. It's just there for completeness' sake
Ah no worries! Thanks for helping and untying the knot in my brain 🙂
Glad I could be of some help
well, Im not 100% convinced yet. Because the scenario: ---+- has "only" a chance of 0.3^4*0.7 of occuring, right? We still want to include that as well
if it was only about losing 3 times and winning the rest you are certainly right
Ah you're right! I completely missed that
but youre right, order doesn't matter! Didn't see that clearly. Honestly I am thinking about closing the topic. I just guessed that it should be doable with high school lvl stochastics, but the more I think about it the more I think it might be uni-level stuff
Idk what necessarily constitutes as high school maths but I think the solution won't be too ridiculous
well, I leave it open then 🙂 but it sounds just like a math problem of high school where I fail to see the solution...anyway thanks for helping!
this is hopeless
@dark kiln You mean to discuss it here further?
no sorry
no problem. I'll probably have a look again tomorrow
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are 0.999... and 1 the same number?
yes
but why
the first question you should ask yourself is: what does the notation 0.99999.... even mean
This is not a proof before you have a clear definition of what "..." means in this context and that a consequence of this definition is that 10 · 0.999... = 9.999... and 9.999... = 9 + 0.999...
Okay that's not an elementary proof, but let's call it an algebraic argument which "helps" to understand the process
@proven nebula Has your question been resolved?
huh?
im confused
think of number between 0.999… and 1
you can always find a real number between two distinct real numbers
eg : between 1 and 2 you can have a distinct real number by just averaging ie 1+2/2=1.5
between 1 and 1.5 you can do the same thing 1+1.5/2 =1.125
and you can continue
shouldnt there be a 0.0000....1?
infiniteismal?
why?
Yes, it is infinitesimally close to 0
no it isnt
Such a number doesn't exist
But yeah, it's probably the best to write down what $0.999\dots$ is even supposed to mean. [0.999\dots \coloneqq \sum_{k=1}^\infty 9 \cdot 10^{-k} = \sum_{k=1}^\infty \frac{9}{10^{k}} = 9 \cdot \sum_{k = 1}^\infty \frac{1}{10^k}] Now $\sum_{k = 1}^\infty \frac{1}{10^k} = \sum_{k = 1}^\infty \l(\frac{1}{10}\r)^k$ is a power series with $\l|\frac{1}{10}\r| < 1$ and thus we have that its value is [\frac{1}{1 - \frac{1}{10}} - 1= \frac{10}9 - 1 = \frac19] (where we need $-1$ because the formula only holds starting from $k = 0$), and thus [9 \cdot \sum_{k = 1}^\infty \frac{1}{10^k} = 9 \cdot \frac{1}{9} = 1.] That's one possible argumentation.
you would need to use limits then
this gives off the idea that its “infinitesimally close to 1”
wha?
An infinite sum is a limit 
you can have no number between 0.99.. and 1
why
think about what 0.99… means
1/3*3
i get that
but shouldnt it be a paradox
dont use tht
no need to use limits either
Well we can argue completely differently too
we can?
i dont really like this since you need to first define what the infinite series “converging” to the number actually means
i dont really like this since you need to first define what the ... in 0.999... means and what real numbers are
this gives off the misconception that there is 0.000000000..1 between 0.99.. and 1
maybe there is
there isnt?
how would you know if you dont have a definition of the real numbers
In mathematics, 0.999... (also written as 0.9, 0..9 or 0.(9)) denotes the smallest number greater than every number in the sequence
(
0.9
,
0.99
,
0.999
,
…
)
{\displaystyle (0.9,0.99,0.999,\ldots )}
. It can be proved that this number is ...
the fact that there is no number between 0.999... and 1 is a consequence of the archmedean property, and can fail in other number systems
so you need to know, as denascite began with, what 0.999... means
and what the real numbers are
doesn’t 0.99… literally intuitively mean you can’t have a number between that and 1
you need to explain this concern
at least if you extend to the hyperreals, thats not a crazy thing to say
so if there’s 0.000000..1 lying somewhere => 0.99… is terminating right?
no?
why
Both could be not terminating, one could think
maybe i have a digit which is the (ω + 1)th digit
and it is 1
but all ω digits prior are 0
that only makes sense when both are terminating no?
can you just construct that? if you have 0.99… and 0.(w) digits and then 1 , theres always a one-one correspondence to every digit of 9 to 0. you placing a 1 at the end makes me think its terminating at a 1
whats after the 1?
if w+1 =1 then shouldnt w = 0?
(im going to ask a lot of dumb questions)
in 0.000…1 whats after the 1?
and arent the negative numbers before 0 counted?
why are numbers prior w 0
dont worry about it
its not possible in the reals, but only because the real numbers has a precise definition
but im making the point that you need to know what the real numbers are and their properties to give a proper argument discounting the fact that there cannot be a 1 following infinitely many 0s in the decimal expansion of a number
<@&268886789983436800>
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what is f(c)
c is presumably some fixed real number in this case
c is the point at which you are testing continuity
function f is continuous at point c, if those 3 conditions hold
because x is already there, you cant use the same variable twice
and "c" looks more like a constant
e.g. function f is continuous at point 2, if:
- f(2) exists
- lim x->2 f(x) exists
- lim x->2 f(x) = f(2)
c can be any number of your choice
and those 3 conditions then determine whether the function is continous at c, or not
np
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Hi how would I solve this?
Where are you stuck?
I dont know where to begin to solve it
@tawny grotto Has your question been resolved?
faiyrose
faiyrose
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could anyone explain this to me? i am horrible with word problems and im questioning if what ive done already is right 😭
let's say there were x child admissions
alright
so how many adult tickets were sold then?
2x?
yeyes
so how much would x child tickets cost?
6.40x
uhhm
ohh
u r wc
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Can anyone help

I am asking🤨
I wanna solve solve this by considering x+....+x^n a geometric sequence of first term x and common ratio x
sure? You definitely can
though i actually think lhop would be much faster here
It would yes
But I'm trying this method
For some reason I'm not getting the same answer idk what I'm doing wrong😭
n=1+1…(n times)
Show us your steps
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We need to solve the inequality and find the sum of the whole solutions. I've already solved such tasks, but this time the answer is wrong, I'm probably doing something wrong
in 4th step where you messed up
actually its 3rd step
apply the absolute rule instead
solve for both x, 2x-3>-8 and 2x-3<8
that part is right, i think
what's the reasoning for your choice of values for the summation
Can you please explain in more detail?
arithmetic progression
I recall when you have a problem such as |x| < a so you could do -a<x<a
for example, let's say we have |x - 3| < 9, simplify it -9 < x - 3 < 9 then gives us -6<x<12
that was done in their first step
I thought you could divide but I see they subtracted there
wait i see in decimal number nvm
could you tell me where did you get 4.5 from?
The integers in the interval (-2.5;5.5) form an arithmetic progression with the first term -1.5 and the last term 4.5
do you know what integers are?
yes
is -1.5 an integer?
Well, it's a fractional number
not what I asked
What did you mean by that?
it's a yes or no question
no
ok. there's your mistake
you're consider the sum of values that aren't even integers
Omg, what should I do now?
list out the values that are actually integers
which are in the range -2.5;5.5 ?
yes
-2;-1;0;1;2;3;4;5
yeh
and you can use the sum formula for that if you really want
or just add them up normally
S=4+2/2*4=12 the correct answer is 12
thanks for the help
why 4+2
end result is fine, but curious why/how you're plugging in values like that
I think I made a mistake.
I was wrong, the correct answer turned out to be accidental
do you know what
a_1
a_n
n
represent in that sum formula
a1 is -1 ?
no
the subscript here is an indication of the term number
a_1 represents the first term
a_2 the second term
etc...
the number of the member in the period?
wdym in the period?
these are all numbers from -2 to 5
No, it's not quite clear
can you try telling me the value of
a_1 again
a1 is the ordinal number of the number that is in the period (-2;5)
Okay, what formula did you have in mind?
and so, to find the sum of the whole solutions, do I just need to add up all the numbers from -2 to 5?
careful with whole and integer as those are different
whole only refers to positive integers
and yes, I said that you could just add up the numbers normally that way
if you want to apply the sum formula, you'd need to understand it
can you show me this summation formula
you wrote it down earlier
sum of the first $n$ terms of an AP
$$S_n = \frac n2 (a_1 + a_n)$$
ℝαμΩℕωⅤ
what is n and a1b, an ?
n is the number of terms you're adding
a_1 as mentioned earlier is the first term
a_n is the nth term (which will be the last term)
S= 5/2(-2+5)
no, n, the number of terms isn't 5
so, S= 8/2(-2+5)= 12
yes
S= a1+an/2n=-2+5/28=12
missing a lot of ()
what ?
() are needed to clearly communicate order of operations in text
that was done in their first step
for fractions, they're necessary to clearly indicate what's actually supposed to be in the numerator
and denominator
the fraction line in the second line should be longer
but writing without () like that is fine due to the advantages of horizontal fraction lines
the issue I'm raising is that you don't have that benefit in text
if I typed \verb|-2 + 5/2| would you interpret that as \ \
$-2 + \frac 52$ or $\frac{-2+5}{2}$
ℝαμΩℕωⅤ
1)-1/2 2) 3/2 ?
monul its a question
it says "would you interpret that as"
do you know what this phrase means
Sorry
I realized that these are two different tasks and the answer will be different, is that what you meant?
omg, I get it, I would understand this as the first option
yes I see
Thank you so much for your help
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uh..
@finite hatch Has your question been resolved?
@finite hatch Has your question been resolved?
@finite hatch Has your question been resolved?
is this from the artofproblemsolving website haha, is there not an answer key
idk i got sent it
where can i find the solution
im freaking out it is 6 am
is this for a class?
uh idk
its to prepare for a math competition
why are you up doing this at 6 am
australian maths competition
😭
bc i need to get a certificate of distinction or high distinction
and my mum will buy me a car
do u know where i can find solution?
You might be able to find it on artofproblemsolving? Not sure how you would look up this specific question
There's a whole range of other questions you could practice using though, if you wanted
oo ok thank u
good night :F
:D
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I do think I figured it out though
.reopen
✅
oooo
You just need to use the fact that
[\tan(2023x) = \frac{\sin(2023x)}{\cos(2023x)}]
biased_estimatERIC
i would not think of that 😭😭
This part is just the definition of tangent so far
Or at least one of them
Whenever you see tangent, it's helpful to write sine / cosine instead
And then you can use de Moivre's formula to calculate the numerator and denominator
Maybe you should try some easier problems involving it
De Moivre's formula says that
[\cos(nx) + i\sin(nx) = (\cos x + i\sin x)^n]
biased_estimatERIC
Basically it gives you a fast way to calculate cos(nx) and sin(nx)
This way is rather simple
It is a helpful thing to know if you are interested in solving trigonometry competition questions
If you know Euler's formula (e^{ix} = \cos x + i\sin x), then de Moivre's formula is an easy consequence of it
biased_estimatERIC
Once you plug this in and use the binomial theorem though, it just becomes a matter of simplifying things correctly, and you'll get the answer
wow...... to be honest i dont even know eulers formula
ive heard about it though
If you're not familiar with these formulae though, you might want to try some easier problems
in hidden figures the movie
Artofproblemsolving has a TON
hahaha good movie
Like here are a ton of practice problems from american math contests: https://artofproblemsolving.com/wiki/index.php/AMC_Problems_and_Solutions
yes i think i need that..
im in 10th what are these formulas 😔😭
they also have this thing alcumus that gives you practice problems that get harder and harder based on your level https://artofproblemsolving.com/alcumus/problem
yea
getting a car as a present for a math contest is absolutely wild
how rich are you lol
good luck!
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How do I prove this inequality? With z and w being complex numbers:
@lofty agate Has your question been resolved?
@lofty agate Has your question been resolved?
If i didnt do a mistake, using z = r e^i phi and same for w solves it after simplifying a bunch, and using cos(...) <= 1
Also squaring everything can be helpful, and equivalent because both sides are positive reals
I've tried that, but... I didn't reach anything helpful
Ok well heres my very crude working if you want to have a look...
z = x* = a e^id and w = v* = b e^ip
And all the lines should be equivalent
And ignore the second to last line lol
@lofty agate Has your question been resolved?
Hmm, ok, thanks
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2 questions on the text highlighted in red
the radius of V is not specified but we assume it's less than delta correct?
also, for f to be continuous don't we have to say for all epsilon > 0 and not there exist an epsilon > 0
how come we're allowed to "stick" with "there exists and epsilon"?
lastly for the text highlighted in yellow
Am I correct to assume that "as soon as" was used in the past more often and now for current proofs we would use different language, right?
instead of "as soon as" I could replace it with "if"
epsilon is the radius of a ball in V.
delta is the radius of a ball in X.
The point of the first part is that given a point p in X, since V is open, we can find an open ball that contains f(p), and then by continuity we can track that to a ball in X.
If you mean when they write "Since V is open, there exists epsilon > 0...", then they aren't using continuity here, just the fact that V is open.
I wouldn't say that it was used more before. There's tons of other ways of writing this. "if" works, "whenever" also works. It's more stylistic than anything.
so epsilon is the radius of a ball in V and since V is open then f(p) is an interior point
by definition, f(p) is an interior point if there exist a neighborhood contained in V
d(f(p), y) < epsilon shows that there is a neighborhood of f(p) contained in V
is my line of reasoning correct?
asking because of the line " epsilon is the radius of a ball in V"
this is the way my head is thinking about that line and I want to know if it's correct
Yes that's correct. Since V is open, any point in V is interior and so there has to be some open ball centered at that point that fits within V. We pick epsilon to be the radius of that open ball.
oh and one last question
f is a mapping from X INTO Y
the INTO is why we're allowed to say f(x) in V implies x in f^-1(V), right?
I've been taught to see onto as surjective and into as one to one which is why I think this
Hum, I get what you mean, but in this case I think it`s just the way it's written. You don't need continuous maps to be injective/surjective.
If f-1(V) was empty, then there's just nothing to prove, since the empty set is open.
I guess the proof could specify that if f-1(V) is empty, then this vacuously holds, but it's somewhat unnecessary.
okay
thank you for all your help
🙂
No problem!
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a = (1-sinθ)/(2cosθ) 1/a= 2(1+sinθ)/cosθ
find sinθ and cosθ in terms of a
Divide both the equations to eliminate cos theta
i think that we can only use 1 equation
at one time
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@hearty flare Has your question been resolved?
BH
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how do i change my english text and number to bolder ones? like arial text, something with a more visible font
$\text{abc} ~ 123 ~ \textbf{abc} ~ \mathbf{123}$
idioticbaka1824
how do i globbally enable that?
yes this is awesome, can you help me change the font for equations to Arial too?
i got this from a google search
i'm sure you can find something, stackexchange has everything
ive been looking this entire time and before for hours and still couldnt find one, so thats why im asking you
these dont work for me
if you're just looking for a font with better visibility, maybe you can pick one from here
I don't recognise the option onfig. Use ,texconfig to see the list of options.
autotex: Disabled (may be overriden by guild settings)
keepsourcefor: Don't delete source (may be overriden by the guild)
colour: Using the white colourscheme
alwaysmath: Disabled
alwayswide: Disabled
namestyle: DISPLAYNAME
autotex_level: WEAK
To see more detailed information use ,texconfig <option>.
To set an option use ,texconfig <option> <value>.
Using a custom personal preamble with 46 lines!
Use ,preamble to view or modify your preamble!
i saw it already, the point is to set it up as defualt for equations, also these suck
\usepackage{fontspec}
\setmainfont{Cambria}[BoldFont = CambriaB]
\usepackage{unicode-math}
\setmathfont{Cambria Math}
try this
@fossil shoal@fossil shoal
it crashes
hmm okay i don't think i can help you sorry
it's alright, ty
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hello everyone
hi
@light mantle Has your question been resolved?
what
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,tc color dark
You have switched to the dark colourscheme.
Let $B=A^3-2A^2+3A-I$ where $I$ is a unit matrix and $A=\begin{bmatrix}
1 & 3 & 2\
2 & 0 & 3\
1 & -1 & 1
\end{bmatrix}$ then the transpose of matrix $B$ is equal to
pun pun
how can i find B using characteristic equation
,tc color dark
You have switched to the dark colourscheme.
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how to show when a_n->+inf this is true?
What is an?
a sequence
Any ?
general a_n that lim a_n = +inf
how would you show if it was just n and not a_n
idk, just say it's true?
just trying to understand what tools you are supposed to use
like listen the previous question was very long to prove and find a lim and all, and this is just the 2nd question now so I think it's more than just a 1-liner
yeah me too
So you have the limit of (1+1/n)^n ?
I mean I could maybe say lim of the above equals lim of the same expression with a_n=n since they have the same limits and end it there I guess?
a_n isn't necessarily =n
but this is a sequence not a function
like you can find N s.t. with a_N the limit is arbitrarily close to e
yeah that's kinda the idea
I don't understand the terminology, I do wanna use squeeze theorem if I can though
no one said the given expression is a cuchy sequence, also idk how to prove it is
It leads to "Block" a_m between the two expression where their limit is e both
how do I prove?
It will lead to find out its a cauchy one no ?
yeah it is a cauchy sequence
Yeye
and I'm pretty certain $\bN \cup {-\infty, +\infty}$ is compact
artemetra
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what have you tried? we're not a do-your-homework channel
oop
i did all the problems before sending them
i just wanna make sure i understand
i have tried
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I can't figure out how to do this
I tried but got it wrong
You were on the right tracks here
Square both sides
and u will be done
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i need help
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1
and!?
if you can get each circle to cover a square, then you can use pigeonhole
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hello i need help with an algebra problem
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how can i achieve a function/rearrange this equation to discover x?
i tried searching for exponent properties that i can use to rearrange this but couldn't find any useful ones.
logarithm?
you can try convert it to: $2 = 8^{\frac{1}{x}}$
Closer
And then using logarithm
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find the roots of the equation $3-|x|=|x-1|$
monul
so. the correct answer is (2:-1) . I have a solution, but I'm not sure if it's the right one.
@lost ravine Has your question been resolved?
Show your work
- No root
just plot a graph
replace 3 with y
and then draw the graph of y=3
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post the question bruh
do you know the conversion from cups to teaspoons
wth is this sort of question
i think it’s just ratios?
we're never taught these conversion...
hello teachers....
I wanted a help
we're taught integration, differentiation, by our physics teacher... but don't have these topic this year and I wanted to have a good grip in these topics
open another help channel
why😭
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I didn't know about it, sorry
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Hello,
Can someone please help me prove the circle property that the perpendicular bisector of any chord intersects the center of the circle?
(i am bored in summer math school, don't worry, i did not fail)
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Doesn't this follow from circumcenter properties
i tried making similar triangles paralell to the diameter
show your progress, then
the problem is, i cant prove that the intersection point from the chord is equal on both sides of the smaller triangle
show your work so we know what triagnles you're talking about
not convenient rn
huh? doesn't that follow from it being a bisector
i can't prove that the stuff in red is equal to each other
Do you know the property that the perpendicular bisector is the set of points equidistant from the two points that make the line segment
yes
And is the center equidistant from the two endpoints of the chord
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Wanted to know if the proof for number 7 is correct
c is the set of all Cauchy sequences and l^(infinity) is the set of all bounded sequences
<@&286206848099549185>
hopefully i wont study these in my univ
hey bro im gona study CS
will i study these?
univ
Most likely not
ur gonna use a lot of sequences and series
@deep bough Has your question been resolved?
it is what it is... 😦
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(Please don't cross-post the same q in multiple places)
What's wrong with just looking up the definition though as Denascite said lol
Oh, looks like your q has been answered anyways
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I'm trying to compute the variance
I thought that E[X^2] = 1 * 1/2 + 4 * 1/2^4 + 9* 1/2^9 + ....
So I get this sum for that term which I know converges via ratio test but I don't know how to compute its value
oh weird
I assume we just close it back up and possibly reopen it
also why does it say price in line 3
I assume it means prize lol
what if you dont close the box
well then its finite and trivial
it seems overly complicated to do that infinite sum
yea
,w sum 1 to inf of (n^2)/(2^(n^2))
suggesting me to compute it
wolfy can only approximate
post the original bro
the original is posted
it just appeared thx
tbf it doesnt say you close the boxes so im gonna believe you cant open boxes infinitely
you underestimate my dedication to finding this prize
closing the boxes is kind of ehh
you still know that this box has no price after opening it once
so why would you open it infinite times
Because the problem says you pick randomly
yea but sooner or later if you opened at least 3 boxes then in the 4th there will be a price
infinite times doesnt make sense
i love you dedication to calling them prices
isnt this your intro probability/stats class anyway ossie
if anything, the ultimate source is asking your prof
it does if u close the boxes and pick randomly again
😠
just probability
why the hell would you close the box and pick randomly again
but do you change the order of boxes everytime you open
it makes no sense to interpret it that way
do you throw them into the air
if I throw out boxes i've already opened
sure, randomly from among the remaining boxes
its a strategy
it doesnt say from the remaining
😠
i believe you are making it a bigger thing than it is
😠
like your bench press
well feel free to interpret it the insane way if you want, it's your grade haha
my bench press is huge
(joke)
okay now im just curious about how one would compute this series
seen as wolfy approximates, its not computable
it does converges quickly with O(1/(2^(n^2)))
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I would interpret it that way if it was a 2 hour exam and thats the only question
fortunately in that context i guess you could just ask
in this context too, for that matter
X^2 takes on values 1, 4, 9, 16, ...
so its expectation is 1 * P(1) + 4 * P(4) + ..
and P(n)= 1/2^n
yea denom is wrong
your sir speaks wisely
why is this?
That’s a definition
I think it's just the definition of E[g(X)]
Wdym why
Tis called lotus